Nope, my top 12 has not changed since November 8 (the day I caught my perfect Raikou and it entered the team)
It's mainly due to my goal to hit 1 million stardust and keeping it there. Therefore I will control my power ups bit by bit and get these to level 40 once I have the dust.
That said, I intend to take my 2 Ttar (96, 96), 4 Dragonites (100, 98, 98, 91), 1 Rhydon (91), 1 Raikou (100) and 1 Gyarados (100) to Level 40. Most of them are 38, but there are no excuses now.
Blissey (100) and Lugia (87) might make the cut after I am done with the above.