Noted! And the intent was for him to be learning German at Durenmar (though somewhere like Cologne makes perfect sense too) for the past few seasons. Not sure precisely how far away that is off the top of my head. That said, yes, he is traveling with a group, but he can also speed them up considerably.
But gotta finish up the last few years first, so back to the grind!
Just because I did some calcs for when Alba had to travel, I share them.
Regular travel times on foot on that age were around 16 miles (25 km) each day (walking speed), unless we are talking about professional couriers that could double that amount.
For example:
From Irencillia to Durenmar we have around 200 miles, so 12 and half days.
Since it's Mythic Europe and roads arent a straight line, i think that its reasonable to double that time, so 25 days.
If you want to know how much time it will took to go from Durenmar to Tugurium, the distance between both (again, straight line) is 115 miles. So nearly half that time (15 days).
Close enough to pick the date as you desire, I'd say.
Btw, here is where Turgurium is irl.
Note that those travel times are calculated in good conditions, during the summer. If you have to carry some of your supplies in a cart, it's raining or the snow hasn't melted in places, or if you need to cross forests, then travel times can quickly increase.
For example, the Black Forest covers a fairly wide area and is hard to cross. There are no roads in there. Some may be able to travel through it, but for those travelling around this can triple or quadruple the travel time. In the winter, this can mount up to ten times as much time.
A minor point, at 1207 Waddenzee was called Terschelling. According to GotF p.66:
"A vote was taken as to whether Waddenzee was a new covenant, and therefore required the permission of the Tribunal to form, but the support of the Oak and Ash Gilds prevented this eventuality."
The current primus of house Bonisagus (and therefore the Praeco) is Avarret of Bonisagus. Going canon, he will chose Murion over Occultes as the next primus in 1213.
What suffices to be a Rhine magus? Membership of a covenant is not required, since there are many peregrinatores in Rhine and they can vote. We just need to declare our intention of joining at the Tribunal?
If so, maybe we should have someone convince Avarret to make our case (us joining the Rhine) the first of the Tribunal, so that we can vote (and negotiate our votes in exchange for sponsorship).
If a new covenant is found, all Magi whose name is on the charter are members of the Rhine Tribunal, since a peregrinatores doesn't have his name on a covenant's charter.
But to be recognized, we need to have a member of each existing covenant sponsor us, and at least one magi from each Gild.
Corrected on the Notes and Claims post.
I don't see anywhere that sponsorship from the guilds is required. Just a sponsoring magus/maga from each covenant (GotF p.16, On the Founding of Covenants).
Yep, just a sponsor from each covenant for us to establish a new covenant.
But I'm actually concerned with the criteria for being a member of the Tribunal, but without a covenant. This may be relevant for voting, since you can only vote if you are a member of a Tribunal. It wouldn't be an issue for Alba and Celeste (probably), but all other magi are coming from other Tribunals.
Clusius was registered as a guest of Triamore (essentially a peregrinator), so would be considered a member of the tribunal as well.
EDIT: The residency question may still be something that comes into play for some magi, even him. But the timing of recognition from the Tribunal is of some importance. Lobbying Avaret (the praeco) to be acknolwdged early during Tribunal might not be a bad idea. 
Vorsutus may (I may be wrong here, but I'll take a shot at it) be temperamentally best suited to dealing with more aggressive/not-nice types like Dankmar and Waddenzee. I'd be open to stories to develop/pursue him trying to come to an understanding with those Covenants regarding a sponsor and perhaps more. Dankmar as our neighbor we would benefit from a better understanding/arrangement with in particular. But Vorsutus would be open to trying to develop a deeper relationship with either/both as his initial foray into building alliances in the Tribunal.
Certainly a possibility.
For now I am more focused on determining for which covenant we will need a story to secure sponsorship, so make sure to complete the Notes and Claims post about contacts and relationships with the covenants of the Rhine. This will help the troupe identify those areas of weakness, as opposed to those where letters will suffice.
Regulus has no particular ties to any covenant or gild. Quaesitorial presence is weak in Rhine, so his arrival would probably be met with the support of the handful of existing quaesitores (by 1221 there are two Guernicus, but both are young and should have arrived only after 1211, so at 1207 it's possible that Regulus is the only Guernicus on Rhine. The book mentions other 2 quaesitores, both archmagi, one in Durenmar and the other in Crintera, but the Crintera one is likely to be in final twilight (no one knows)).
I've updated the list of covenants with some general info (between Regulus research at the library and the shared knowledge between us all I think it's reasonable for us to know at least that much.
@RafaelB you updated the Notes and Claims, but without identifying your magus as the source of the contacts. Please do so.
Otherwise, we'll get a confusion of who those contacts and potential sponsors know. Also, simply belonging to the same Gild isn't really enough of a reason to approve a new covenant. A stronger relationship would be required, either on a personal or political level.
Humm, sorry. I will move that content here then. My intent is for us to have a grasp of avenues of approach (given information we could reasonably known) outside of our personal relationships. I agree that membership of gilds (or intent to join) is not enough
Is your understanding then that sponsorship from Triamore and Fengheld is already guaranteed?
Decided against just copying everything from there, as it would be a bit useless. Just a few thoughts:
Not guaranteed, but probably easy to achieve... unless we want to initiate a story about why, despite close links, those potential sponsors would decide not to support Tugurium.
These are Clusius connections, so if you want him to go on solving these problems... =9
Seriously, do you want to? We can explore this. I'm already cooking something in my mind while we talk... 
As an aside, I'm thinking of having Regulus spending a season or two travelling the Rhine to settle conflicts before Tribunal. If anyone wants to run a story centered on either hermetic legalese or hermetic investigation, there's your chance. =]
This could also result in the sponsorship of a previously neutral covenant.
I added a note on Oculus. They are Vis hungry, so buying goods from them, like a magical ship, from their shipbuilder Verditius, or even mundane goods, or copies of books, in return for Vis, could help secure their aid.
Don't know if Terchelling's change of name is something Celeste would be aware of. It might be something Eric might mention in his letters, if they've kept in touch.
I could see a story with Dankmar, possibly with Celeste going there to secure their aid. Was thinking about her going there in 1205, but not sure if that's too many covenants she'll have some ties in. The idea was that their defense is somewhat enticing to her, and their dark brooding vibe, but that something there would go well, and she'll leave. It might complicate things when she goes there to secure their help, but hey, what's lfe without some bumps on the road?
Hey @Vortigern you hear this? A magical ship builder! Now who do we know that might be interested?
Plus we could really really use some better books, so that's always handy.
That said, Belisarius is definitely going to be going out to acquire more vis in the near the future for precisely this sort of thing, so color me interested.
It's not simply a change of name, it's a wide political movement that started around 1201. You can see it as a "Ship of Theseus" kind of thing. If you change "everything" about a covenant (symbol, name, magi, goal) is it still the same covenant? But yeah, maybe Celeste wouldn't know.
Still, either someone from Tersch/Wadd could approach us, or a member from the Oak/Ash gilds (since it's stated in GotF that due to support of these gilds Waddenzee managed to get by). Maybe the way this support manifests in our saga is "an Oak gild member from Crintera promissed to sponsor us as long as we vote with them on this matter".
I don't think we would want, as a covenant, to buy a magical ship (maybe a magical boat at most) since we have no easy access to the sea. Maybe particular members of the covenant would? On that note:
Who? I'm curious. =9
If it's something they started in 1201, it could be that Eric made his connection with Celeste purely, or partly, depends on how people want to run him, for that reason, to gain another vote for the change.
In that case, he might well have kept in contact with her, to try and secure one more vote. especially if the change is only narrowly passed, then every vote counts.