Well, my flight departs in 40-odd minutes (TG 410 SIN-BKK) and it's a 774.
So, I tried to request for a 'seat in row 1 or 2' - the SATS agent could not do it by herself, but she called the TG counter without prompting and they allowed it immediately.
Thus, I think it's fair to conclude this is an 'unpublished' quirk despite preferring to leave the F cabin untouched.
I'll be in 2K but it seems I'll be able to do it solo.
Will report back on the load later (and also take a look at the UD J cabin). Never been on a TG 744 before! Quite excited!
(Oh, and when trying to OLCI earlier today, all the F seats were blocked out. Only two were selectable in J)