Hello
I am having the exact same problem did you come up with a solution to this in the end?
Contiually rasterize not only disables (preserving the nested frame rate of a comp) but it also seems to have issues when you use a posterize time effect with a camera.
Any solutions would be very much appreciated.
thanks in advance.
UPDATE & SOLUTION:
1: Instead of using posterize time as an adjustment layer you can add an expression to the property you wish to change the frame rate of (i.e. position) by pasting this code in the expression field of that property. This will then posterize your keyframed animation on that property to whatever you desire by just changing the number in the brackets. I found this code on another forum.
posterizeTime(1);
value
2: If you wish to have a wiggle expression with a posterize time effect on the properties layer (i.e. position) then fabian the blind has made an awesome script to do just that, Link below.
https://fabiantheblind.github.io/wihihihiggle/