The stipulation is 65k per calendar month. It doesn't necessarily have to be one payment of 65k but that makes life easier for the IO, so it's best not to upset them. When I started I was doing 2 x 33k which was acceptable, and one time the exchange rate changed before the money hit the bank account so it came through as
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, so I made another transfer of 200 to push it over the threshold. It was acceptable