This isn’t so much a change in policy as a change in procedure. Up until now (or at least while I’ve been approving memberships), acceptances for future publications haven’t counted toward the membership requirements. In other words, if a writer had a story accepted to an anthology and needed that credit to count toward the membership criteria, they’ve had to wait for that anthology to actually be published before being accepted as a member.
From here on out, though, if you have a signed contract for the story or book in question, that can be counted toward membership. (If the market doesn’t do contracts, you’ll still have to wait for actual publication.)
I’ll be updating the website soon to include this.