Staff distances

Hello! My question is as follows:
I'm writing for a trio (violin, cello, piano).
I have set staff distance = 6sp and grand staff distance = 8sp (for the piano).
In this way, I have 6sp between violin and cello and 6sp between cello and upper piano staff.
I would like to widen the space between the cello and the first piano staff to 10sp throughout the score, in page mode.
When I use the "staff spacer down" in the first system, it affects only this system and not the rest of the score.
I have a score of 300 measures, so clearly it's out of the question to use spacers in each and every system.
So, is there a way to modify solely this exact staff distance to e.g. 10sp ?
Thank you!