We used the online check-in about a month ago right after midnight.(Actually, I made my 19 yo DS do it for me as he's usually up that late, not me!) There were 4 of us and all of us got A passes. Of course, there was the usually zillion preboards, so it didn't help a whole lot as we ended up in rows 13 anyways.
Coming home from WDW, we didn't have access to a computer, so got stuck with "B" passes on the way home. The person who checked us in told us we didn't need to print the passes, but just check-in online and they could have printed the passes for us. Had I known that, I would have had one of my DS's left at home go online and check us in right after midnight, to give us a better chance at an "A" pass.
Of course, the "A" passes don't mean a whole lot, due to the number of preboards - that's the one pet peeve I have about SWA. I feel if families want to sit together, they should have to be there early, just like the rest of us.