From the official AO-27 website http://www2.umbrasi.com/
*June 28, 2015* AO-27 Turned on today. Seems good on the bootloader If anyone has contacts into CelesTrak to get AO-27 back into the amateur.txt file it would help some of the control operators stations. Our e-mails have gone unanswered. - Michael, N3UC - Dan, KM4HZJ - James, N3UCC
Dave Webb, KB1PVH, sent a tweet earlier this month to @TSKelso at CelesTrak and AO-27 is back in the list. Control operators can now track AO-27 and attempt to load high level code.
It is very important amateur radio operators DO NOT USE AO-27, the satellite is in MAINTENANCE MODE ONLY. Attempting to use the satellite or randomly transmitting on the uplink frequencies as the satellite passes nearby does interfere with control operators attempting to upload commands and software.