Alfgar's Start Date
I suspect the start date of Alfgar may be incorrect, as heraldic missives such as this are still addressed to Sir Koppel in January 1972 (they also give Koppel the title Mural Herald):
--Mathghamhain Ua Ruadháin 11 May 2018
One possible source for the February 1970 start date is this letter, which shows him as "Pursuivant" -- but that does not make him the Principal Herald or Brigantia as of that date.
In June 1972, Alfgar is listed as "Acting Principal Herald" in this letter:
The first mention of Alfgar as Brigantia in the Laurel letters dates from December 1972.
Submissions started by Koppel as Principal Herald were still under discussion in June 1973.
I think that further supports revision of the start date.
--Mathghamhain Ua Ruadháin 3 September 2020
Furthermore, in the May 1971 Laurel Letter cataloging the earliest armorial registrations in the East, Koppel and John of Brook Lynn are listed immediately after the kings, with dates of service as Herald with John starting 19 January 1969 and transferring to Koppel on 1 February 1970; Alfgar is listed much further down as Pursuivant.
--Mathghamhain Ua Ruadháin 4 January 2021