Problem converting ASR920 from traditional to smart licensing

Hi,

I have an ASR920 with local licenses, which we would like to convert to smart licensing. We've done this many times for other devices (ISR1100, 4300 etc.), so we're not exactly new to the process.
Smart Licensing is enabled on the 920, the device is registered and has attempted to get the currently (local) licenses from the server. Anyway, the "license smart conversion" command is not available, all I get are the commands clear, deregister, export, factory, register, renew and send. What am I missing here? IOS version is 16.12.5 ...