Brace spanning any amount of staves depending on the system

So I have this piece for solo piano where there is one measure without the third staff, then the next with the third staff at the bottom, but I hid the third staff in the first measure mentioned, which makes the brace span the three staves despite only showing two. If I try and change the span of the brace, it ends up not spanning all three in other systems. Is it possible to make it span just two staves for one system, and then go back to three afterwards? Or better yet just make it span however many staves there are on the instrument?