It's not really that complicated... Even if you have up to fifteen boxes per person that holds about twenty pokémon, that's three hundred right there, not including evolutions or who is in your party.
Even when you're having people arrive all the time, you have others that are leaving. All it should take is overriding the name on the account and releasing what's already in the boxes.
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Even when you're having people arrive all the time, you have others that are leaving. All it should take is overriding the name on the account and releasing what's already in the boxes.
That's only like maybe an hour's work?