The government's UK copyright law site outlines the IPO and Copyright, Designs and Patents Act 1988, the principal legislation covering intellectual property rights in the United Kingdom and the work to which it applies.
It's not that I have to wait for payments to reach the threshold, it's that unless each
individual placement is over $50 they no longer pay at all.
So if I had 1,000
placements that were each for $49 (something that could certainly be likely with the low
amounts they now seem to charge their clients) I still get zero.
But yes,
unless they pay me what I'm owed, I'm off.