I thought it would be fixed in today's patch, but maybe I missed a change in the patch notes last week? I have been in 4 BG matches since Anniversary Event started that mixed over-50 players with under-50 players. Once my character was level 23, which made it super hard to do anything when players on the other team were over 50 and high CP. Oddly enough, I got kills and won 3 out of the four matches, so not sure if this is WAI now. If it is, I would ask you to take the restrictions off monster sets and arena weapons for transmute. Other than having many more skill points and skills unlocked, the monster sets and arena weapons only being usable for over-50 is an unfair advantage. I am guessing it is a bug, but just in case...