Hi
The radio will be able to find the sync word. We usually refer to the 0xAA part as preamble and the the following bytes(0xD6 in your case) as sync word. I understand that both our preamble and sync word is both 8 bytes, 16 bytes total. If you set up the CC1101 to look for 32 bit sync word of 0xD6 0xD6 0xD6 0xD6 you will be able to freeze the RSSI on sync detect.
Be advised that if you send 8 bytes of sync word and look for 4 bytes, you will get sync on the 4 first bytes after the preamble (the 0xAA's).