I thought it was going to be a problem when I gave up the IP I've had for a mailserver at hoster A for 15 years and moved to Hetzner, but it wasn't. But of cour

I thought it was going to be a problem when I gave up the IP I've had for a mailserver at hoster A for 15 years and moved to Hetzner, but it wasn't. But of course that's only anecdata, like everything 90% of personal mail server operators will tell you, no one runs several different setups at different IPs/hosters.