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rapid pvst ignoring TCN from garrett-comm switches

I have a simple setup with a 3560g set up as a root switch with default Vlan 1 and three garrett-comm switches running RSTP. I'm not sure what is going on since I haven't used rapid-pvst before but the topology is a ring and I do not see a convergence or mac accelerated aging event when a particular segment is disconnected. I have run debug to see the recieve BPDU's from the GC switch and can see the TCN bit set correctly. The 3560g basically ignores this BPDU and doesn't treat it as a topology change at all. I have attached a PDF diagram to explain in detail. Essentially I create a failure between port 9 & 10 on 6K-A and 6K-B and the MAC on port 28 pointing to 6K-B only refreshes after the default 300s. I never see any TX BDPU's acknowledging the topology change in debug. I see all the proper BPDU events from the GC switches but the Cisco only sees a topology change when an adjacent segment is disrupted. Any help would be much appreciated.