Do a shut no shut on the ports to power cycle the AP's, just to be on the safe side.
Note: I would statically assign IP addresses to your AP's - it's good networking practiceIf you are able to be on the same network as the AP's you should do a wireshark sniff during a power cyle of the AP to determine it's IP address as you'll see this via the ARP broadcast.
You can accomplish this by using the "eth.src == " filter option:
Additionally you should see if the DHCP request is being made and also if its successful or not, which will help with your troubleshooting.
Good luck