CTS with 7975 IP phones OBTP

[rpadfield]

Hi,

I am currently in the process of migrating CTS systems from one CUCM to another and in the process enabling OBTP.

The CTS codec and phone register correctly, and the phone is subscribed to the correct services, but I only get the 3 softkeys on the phone's display.

When it should look like this:

Software versions:

CUCM 11.5.1.10000-6

7975 phone SIP75.9-4-2SR2-2S

Phone subscribed to TSPM-1.10.0-P1-1S

TMS Version: 15.3.0

TMS-XE 5.3

Meetings schedule ok, but do not display on the phone.

What am I doing wrong?

Many thanks

[Bufesrac]

Has anyone got a solution for this issue? I have 2 CTS-1300 with 7975 phones which have the same configuration on the same CUCM and one has the meetings on the IP phone (in fact dozens of them) and the other has the screen posted by rpadfield. I have verified that the meetings are pushed down to the CTS-1300 by checking the CTS-1300 logs (nv_logs_coredumps_SRCalendar.xml), but those still don't show up on the phone. 

CUCM: 11.5.1.12900-21

Cisco 7975: SIP75.9-4-2SR3-1S subscribed to TSPM-1.10.0-P1-1S

CTS: CTS 1.10.15(4) P1