I don’t know if this is by design or if it’s a bug, Nuendo 14 (latest version).
I have a project that starts with 3/8 time signature. Half-way in it switches to 4/4 on the a signature track.
When setting the pre-roll amount to this:

… the pre-roll after the signature track has changed to 4/4 still jumps back 3/8 instead of the full bar.
Any ideas? Now I have to manually calculate the pre-roll based on 8:ths every time I want to record in a different signature of the project.