If the mail reaches me then AFAIU it's legal. A contract does not stipulate that I must spend nights at the address I provide. How, for example, would you otherwise deal with having two residences?

While you may have multiple residencies, legally you have one domicile. This is the location where you live and verification of you actually living there is required by most contracts and is enforceable in a court.

Unless of course you don’t live anywhere because you move every 4 weeks.

Turns out our society is really not designed for someone without a physical residence. It’s made for a frustrating year for me.