A bit of both....
Currently the transfers page is only on the SQL webmap, so would require an SQL server. Though Herr Burt's editor may have this capability soon to edit a characters race on a non-live flatfile.
In either case, flatfile or SQL, adding races after the server start would require db edits to the racelist. (unless you intend to start the server with all six races in place and just ask people only to login on the designated races for each week)
Or, as you imply you could run 4 separate servers incrementing the starting PP for each weekly start and edit the map to match where last week left off...
Perhaps more masochism than genius or insanity...