I have a huge configuration of an application development server that needs to reboot a few times.
I've configured the LCM with 'RebootNodeIfNeeded = $True' and I'm using xPendingReboot to control the reboots throughout the config. I'm not using a pull server.
At some point in the config I don't want the node to auto-reboot anymore. But AFAIK I can only change the RebootNodeIfNeeded setting by running Set-DscLocalConfigurationManager again.
It's really not. You're correct in that you have to reconfigure the LCM, and you can't do that while it's processing a configuration. The most you could do is manually inject a new meta-MOF, but it wouldn't be processed until the next run.