[reustle]

I'm guessing this is common practice, or tooling is available, but could you set up essentially fallback DNS to your own servers in the case of protonmail servers not responding? Should you have some middle server that does smarter routing based on the status of the final server? I guess you're nearly running your own mail server at this point, though.

[valera_rozuvan]

I am leaning more towards just owning your own domain name, and using that for your e-mail address. I.e. configuring custom domain for e-mail. This way, if your current provider goes down (for the long run), you just go to a different provider, and configure your existing domain name for the e-mail. You don't have to change your e-mail address at all this way!

Yes, you could also run your own mail server, but this is not my point.