Hello there!
What are the issues about not being officially recognized by the Tribunal? I ask because at the start of 1220 Heorot hasn't been recognized and I wanted to delve into what that means. GoTF says that an unrecognized Covenant "doesn't legally exist," and specifically references claiming vis sources. What other problems / lack of privileges does Heorot suffer from?
I think we can infer that, without covenant status, they can’t claim vis sources.
If the magi don’t have a covenant, they probably fall under the category of peregrinators under the Rhine’s peripheral code. We don’t know a lot about what that entails, however.
One thing we do know for sure is: since they aren’t a covenant, they don’t have a say in the founding of other covenants.
They’re also missing out on resources. By tradition, every covenant in the Rhine gives a gift to a new covenant and these gifts can sometimes be quite lavish. Heorot hasn’t received these.
There are also probably political considerations. Other magi might look down on them and be less likely to, for example, sponsor their rise to master status.
Some Tribunals award specific rights to covenants, limit speaking to known covenants, and otherwise part out non-covenant magi.
You may not be considered a member of a given Tribunal if you are not in a known/recognized covenant. I don't think a 'guest' mage/peregrinator/eremite can be denied access to Tribunal, but they don't have to be informed (the Redcaps might inform them anyway) and can be generally ignored. You have the right to vote, though; that's Code.
A covenant may have specific or superior rights to vis sources, territories, magical and other resource, compared to a lone mage, and if you're not in a recognized covenant, you're a lone mage, no matter that there are a dozen of you living together.
You won't get recaps delivering mail or announcements to you. You may not be notified of things happening at Tribunal, and if you do turn up to Tribunal meetings it is unclear whether you would be able to count a wandering peregrinator and able to vote or whether you'd be denied voting rights as you couldn't prove residency in the Tribunal. You probably won't be allowed to take apprentices as the Rhine reserves that right for Masters resident in the Tribunal.
"I will abide by the decisions made by fair vote at Tribunal. I will have one vote at Tribunal,
and I will use it prudently. I will respect as equal the votes of all others at Tribunal."
So, they have to let in at Tribunal, and your vote counts, but that's about it.
Of course you could always apply to be a chapter house for a covenant in another tribunal...
or leverage such a suggestion into being recognized.
It's very common not to be part of a covenant: "typically around a sixth of its [the Rhine Tribunal's] magi are peregrinatores." [GotF p.20]
Redcaps will deliver mail to you: "Redcaps must do their best to ensure that all magi in the region receive this information [the Tribunal invitation] with enough time to make arrangements to attend." and "No matter how many magi live in one place, every address is considered a covenant, so long as the Redcaps have a record of it." [HoH:TL p.83]
You don't need to be part of a covenant to train an apprentice: "Once they achieve the status of master, they will, unlike others, typically remain a peregrinator for a couple of decades; enough time to train at least one apprentice in the traveling tradition on the road." [GotF p. 22]
I'd say that, barring specific rulings like those of Normandy, vis sources can belong to individual magi, not necessarily to Covenants.
So I think that the only thing a bunch of Rhine magi really get from having their Covenant recognized is that they can have a saying in the founding of other Covenants (and of course, by tradition when a new Covenant is founded you get gifts too).
There is a catch though. With a frontier Covenant such as Heorot, its recognition as a Rhine Covenant means that its magi are recognized as Rhine magi, and that its territory falls under the jurisdiction of the Rhine Tribunal. Which may not otherwise be the case!
I expanded on this in Peregrinatores (since a big part of that is the struggle to found a covenant). GoTF says "no collective rights", and other posters have already talked about applying that to vis, but there are two other implications: an unrecognised covenant can't enter contracts (FWIW), and it cannot own property, including their own site.
The latter is a significant vulnerability. Covenants are recognised as having ownership of their sites and the right to exclude others, and interfering with this ownership is deprivation of magical power.
An unrecognised covenant enjoys no such protection, and any magus or covenant can settle there. In the latter case, the covenant’s ownership will be legally recognised, and the current residents forced to move.
The residents of an unrecognised covenant still enjoy their personal rights under the Code, including the right to personally own property and the right to a sanctum. But if another magus establishes their sanctum on the same site, they must either accept their new neighbour, persuade them to leave, or use certamen to force them to depart.
Being able to control who you live with (and have some means of binding collective decision-making to stop them doing stupid stuff and ruining your life) is one of the chief reasons to become official.
One reason this might matter more in the Rhine: because junior magi must defer to their seniors in any matter resolvable by certamen.
Disputes over the ownership of vis sources are common. If neither party has registered with the redcaps (allowing ownership and priority to be definitively established), then they are normally resolveable by certamen. Which means journeymen lose every time regardless of the facts.
A covenant however has a distinct legal personality, and as disputes between covenants over vis ownership are still resolved at Tribunal, they must sit outside the Rhine's social scale. You can't challenge a covenant to certamen, so disputes have to be resolved by law. And that's a useful protection to have.