I have done a search on Tribunal in this forum, and a search on Tribunal Calendar on the net, and haven't quite come up with what I'm looking for.
(Note: Yes, I have no 5th edition material up to this point.)
In 2E-HoH, p. 42, it lists Tribunal meeting for 1227, 1235, 1242, etc. Just a short distance up the page, it says the first Tribunal was on 767.
On p.40, it lists some Peripheral Code rulings (the dates in 4E-HoH are pretty much the same). The first is in 767 (906), and that makes sense. The second is in 773 (912), only six years later.
I was under the impression Tribunals were held seven years apart, but it appears that the second Tribunal was held 6 years later.
The third ruling is in 799 (938), only 26 years later. 26 is not divisible by seven, six, or a combination of sevens and sixes.
I created a quick by-seven-years list in an MS Excel spreadsheet, showing AD years and Aries years side by side, buidling on AD 767 and Aries 906 as the starting dates.
The 2E-HoH p.42 dates for Tribunals are all one year off, which would make sense if the second Tribunal had been off by one year, as its date shows from the Peripheral Code rulings, except that the dates some of the later Peripheral Code rulings don't match any Tribunal date (offset or not offset); with the exception of Grand Tribunal dates (counting backward from 1228).
The closest "correct" dates the spreadsheet shows to the "third ruling" (2E-HoH p.42), on AD 799/Aries 938, are AD 795 (for a non-offset Tribunal list), and AD 794 (for an offset Tribunal list). (And AD 802 and 801 afterward).
I didn't spot any references in ArM4 or 4th Ed. HoH to help out.
Rather than run myself around in circles on this, can anyone tell me what is going on? (Viz-a-viz the dates being offest in the calendar listings and the Peripheral Code ruling dates not looking right.)