This is just an educated guess. But there is a certain sequence, and it is based on server-wide rolls.
Not too sure about other servers, but for TW. If you are to roll capsule 27 in wee hours or something. IIRC, once you get a T2 from the cap, the next roll will almost certainly be a Wing. Shows that there is some sort of order to the roll. However, it is very likely to be affected server-wide.