I was working through a factory reset process on my Cisco 8945 phone and after the reset completed successfully, the phone attempted to download the latest firmware version from the device defaults page. The phone froze after powering on each time. Like usual, the fix was pretty straight forward.
Within the 9.4(2) release notes that are associated to the firmware version of CUCM 10.5.2SU2a, it states that the firmware can only be upgraded from 9.3(4) onwards.
After a quick upgrade task, the firmware was statically set on the device. After a a restart of the phone, the 9.3(4) firmware was loaded.
As a side note, the device defaults were reset after the *.cop file upgrade. Below is an image of the settings after the *.cop file install and the default settings. While there was a delay after the upgrade and the reset of the 9.4(2)8 settings, my other 8900 device did change firmware versions.
The final step was to remove the 9.3(4) configurations on the phone and/or device defaults followed by another reset.