I had 2 layers precomped. One was a hand, the other was a luma matte for the hand. After i precompted, i added time remapping to speed up slightly. But only one layer sped up, the other stayted the same. Making my hand look...well you know....Rasterize button was off, it was not 3d, no layers were 3d in the comp. I had to render it out, replacing the comp with render, then time remapping worked.