UAVCAN v0 is currently in the legacy maintenance mode and it will see no further development. New projects should adopt UAVCAN v1, which rules out UC4H. The PX4 team is currently working on supporting UAVCAN v1 and it is expected to be available in the foreseeable future (I am not in a position to provide any estimates, it’s best to consult with the PX4 devs directly).
For interfacing your analog servos with UAVCAN consider building an adapter node based on 107-Arduino-UAVCAN. You will find relevant documentation on the project page and also on this forum (use search):