Not really fixed yet
You still get 5 STR bonus at first level of weapon mastery
There is a shot with 1lvl archery mastery and 255 statcap, not wearing any items. 110+108+42=260 so there is still bonus 5 STR
Next one is taken after changing mastery to bushido, for example.
And another one when switched to Archery (1) again.
Again, 1st level of weapon (archery) mastery should sypply you with just 5hci. There is a slice from uo.com also.