Training sequences of ARFCNs different than C0

Hi All, I've started implementing reception of multiple channels of a BTS as part of my gr-gsm project and I encountered little problem. C0 channel (most probably) uses different training sequence than the rest of ARFCNs from Cell Allocation. I'm not sure that this is the case. But if I compute cross correlation I always get the strongest peak for a different training sequence. The training seqence number used on C0 is usually equal to BCC (BTS Color Code) that is transmitted in SCH bursts (I've never seen different situation in the wild). I can also find training sequence code of C0 transmitted on BCCH inside of Channel Description in System Information Type 4 messages. Where BTSes transmit training sequence (/sequences) of ARFCNs other than C0? Best Regards, Piotr Krysik