Ofono (at least for ublox) is always powering off the radio during start.
This can of course be handy of programmatic reasons to bring the modem to a known state.
Some configuration requires the radio to be turned off;  for instance the LTE auto connect APN. But on the other hand these are stored in non-volatile memory and could be configured before hand.

The big drawback with turning it off is that it might take time to register again when the radio is on. I have seen it taking more than 10 minutes in extreme cases.

In embedded systems this can be a big issue.

I'm thinking of adding a configuration option to keep the radio on during start.

Whats the general thought about this?