I have a 2005 Subaru Forester 2.5x non-turbo with 92k miles and I believe the separator plate may be leaking. The oil leak is in the middle, towards the rear of the engine, where the engine and trans meet. I also have a head gasket leak, on both banks, and I plan on replacing those as well, but I want to prepare accordingly. Any help is appreciated.
As far I can tell, there was never a definite switch over from the Phase 1 (plastic) plate to the Phase 2 (Aluminum) plate (you can't get the aluminum one now, but the pressed steel version is just as good). The plastic plates - as you probably know - had a tendency to leak. The aluminum and steel plates don't leak unless they were installed incorrectly (usually as a replacement for a plastic version, and all the sealing gunk hadn't been removed, so the seal wasn't good).
General advice is to factor in a replacement seal if you're going to reseal it (less than $50) - because there's a good chance you'll bend the original seal when getting it off.