In our current situation we have a mainline with some functionality we want to branch (A). However after branching we want to replace the main line by a different branch line (B) (we cannot merge it, we have to replace it).
Before situation:
|--------------- (Branch B)
---------------- (main)
|--- (Branch A)
After:
-----------------(Main, previously branch B)
--- (Branch A)
Since Branch A's parent (the main line) was replaced with Branch B, it no longer has a parent. However we might want to add the bit of functionality from Branch A later to the main line again. Is this possible?