and not fifty pennies more

You'd think they'd at least program the cheque-writing software properly. Then again, these days, such things are probably programmed by the generation to whom cheques are weird things used by the preceding generation. Whilst I know where a chequebook is (somewhere in the house; possibly in a drawer, maybe in the filing cabinet; findable within hours, at least) I very much like not having to bother with them a great deal any more, particularly the whole having to find a physical branch of a bank to pay them into (though obviously exceptions will be tolerated when it involves cashing the payment from the dozy motherfucker's insurer) but I at least know that you only put 'ONLY' when there are only an integer of pounds, in order to prevent anyone writing anything extra after it and stealing up to ninety-nine pence from you, though that assumes that "one pound and eighteen million, one hundred and eight thousand, four hundred and twelve pence" would be considered potentially enfraudulated, no matter how well-matched the handwriting, though it may be the case that it's been a long time since people paid much attention to the fully-written-out-in-words section, as I've managed to pay bills in the past using constructions such as "and twenty-eight of the Queen's new pence" without being asked by the utility provider for another cheque, written properly.