When running multiple sprints, I need to be able to specify which future sprint incomplete work is moved to

I have a project with 3 teams, we have been using the Classic boards but as these are now on the chopping block I'm looking at the new boards.

I am using the multiple sprint functionality, but the problem comes when completing the sprint.

Say I have active sprints 'A1' and 'B1', then during the sprint I'm doing some planning for the next sprint which are 'A2' and 'B2', when I release A1 on my sprint planning day all the work will drop in to the top future sprint (A2), but when I release B1 that too will drop in to A2.

When I release a sprint I need the option to define which bucket unfinished tasks are going to fall in to, just like the Classic Boards supported.