SRT cache on larger SSD & TRIM

[omniscence]

I currently use a 256 GB SSD for OS and applications and a 64 GB SSD as SRT cache for a 3 TB HDD. This enables TRIM for the primary SSD. Since I will not fill the 256 GB SSD anytime soon I was thinking about using the 64 GB SSD otherwise and just using the 256 GB with a small cache and the remaining part as OS partition. I know that I have to erase the SSD first and create the SRT binding before I can copy the OS partition back. The questions is: will the remaining part of the SSD correctly support TRIM?