Upgraded 8851s to 12.8(1) and am having issues with last line selected

[AnthonyGreene64131]

Hi everyone, I recently have started updating our 8800 series phones (specifically 8851s) to 12.8(1) from 12.1(1) and it seems that this breaks the last line remembered.  I think I need guidance, because from what I have been able to find this is the expected behaviour.  It seems on the 12.1(1), and I have tested this, that when you have say line two selected (whether that is the ipcc extension or just a second line you have on your phone) and make or answer a call and the call disconnects it stays on that selected line.  On the 12.8(1) when you disconnect from a call on your selected secondary line and go on hook it automatically jumps you back the primary line.  

We have the service parameter "Always Use Prime Line" to false and the "Show all calls on primary line" disabled as well.   We also have some 8865s and it is also running 12.8(1) and has the same behaviour.  I tried reverting my 8865 back to 12.7(1) and it also has the same behaviour.  Is this the expected behaviour on this newer firmware and if it is, is there a way for it to remember last line selected? 

[Adam Pawlowski]

Yes - it changes that behavior at some point which seems to change that param . You can revert it by using the Cisco support field with a bugID that tells the phone what behavior to do . I can post it later but I’m not at my computer . TAC can probably grab it quickly if you ask for this. 

[AnthonyGreene64131]

If you happen to stumble accross it, could you post it?

[Adam Pawlowski]

I will soon hopefully, just need to verify something since the details aren't public visible right now.

[Adam Pawlowski]

So, I'm not sure why 100% but based on what I was suggested, please reach out to TAC / account, and ask about the change in behavior for revert to primary line key when call ended , that you want the old behavior back, and they should be able to tell you how to achieve this.