I could have sworn way back when I was newly minted there was a rule that said the amount paid to a mortgage broker when you first took out a loan was not allowable, as it related to obtaining finance and so wasn't revenue, compared to when you renewed the loan later when it was allowable as it was for existing finance. After a debate with a younger colleague I can't find hide nor hair of the rule... all finance costs appear to be allowable (subject to the 25/75 split for 19/20).
Now before anyone gets upset, I haven't had cause to (try and) enact the rule in a long time, in fact I think the only time I have ever done it is in an exam (where I had it in my head as one of the 'classic tricks' to see if you could tell the difference between new and existing finance, like the new/existing knowledge rule). So no clients have been harmed in the making of my delusion. And obviously I now am corrected and know for future.
But for the sake of my sanity, is there a rule in another part of tax I could be thinking of? Or have I just straight up made up a rule?