It's Co-Adjutors that take over when the Ordinary retires. Suffragans get to share admin duties but don't have jurisdiction. I believe at GC2003, there was a vote to amend the canons to give voice and seat to ALL bishops--suffragans and assisting. I believe it was defeated, but has to be voted on a second time according to sacred canons. I'll have to go back and re-read the journal (if I can stomach it, that is).
Ah! Thanks for the correction.