In the past when I’ve had to migrate emails I’ll set up automatic forwarding for anything important like that. Then switch the services you can. Idk if something like that could work for you and it is admittedly a bit of a pain to keep track of. Could limit MS influence on your stuff though
One small problem: some services won’t let me change my e-mail for dumb reasons, thus I’m struck with MS for now.
In the past when I’ve had to migrate emails I’ll set up automatic forwarding for anything important like that. Then switch the services you can. Idk if something like that could work for you and it is admittedly a bit of a pain to keep track of. Could limit MS influence on your stuff though