Took my phone in today for a pre-scheduled appointment and it qualified for both the battery replacement and the recent sleep/wake button replacement. The Apple Store I went to did not have any batteries and they were having to "order" them for everyone who had appointments, advising that they would likely receive their order in the next 2 business days, at which time the store would call them to come in for their battery replacement to occur.

As for my phone which needed both the new battery and replacement sleep/wake button replacement, the store had to send my phone away for repair and they gave me a loaner to use in the meanwhile. They said it'd take about 10 - 14 days for the repair.