Let's say a solid has a stable phase (A) that exists below some temperature, T, and A transitions to another stable phase B above that temperature. If you take a solid sample of B and rapidly quench it such that it forms some metastable phase (A'), then upon heating past T will you see the following sequence:
A' -> A -> B
A' -> B ?
In other words, does the stable phase, A, have to appear between the metastable phase A' and B?