I'm not too worried about stamps with barcodes, however making all the old stamps invalid from 1 February 2023 is going to cause several problems. I asked in t

I'm not too worried about stamps with barcodes, however making all the old stamps invalid from 1 February 2023 is going to cause several problems. I asked in the Post Office about this, and they said old style stamps would be treated the same as unstamped mail from that date. In the UK that means the letter is delivered provided the recipient pays the postage, plus a fine (or a fee for the Post Office's trouble - whichever you prefer). Why is this a problem? In the UK we've had for a long time, stamps just marked First Class or Second Class which are supposed to be valid indefinitely and typically people have a drawer at home with a pile of these. You'll be able to exchange these at the Post Office (tiresome!) for bar coded stamps, however that is going to be a problem for all the Self Addressed Stamped Envelopes in the world waiting for something to happen. Here is a specific example which affects me. Radio Amateurs send each other QSL cards which are personalised post cards acknowledging a radio contact. These are usually sent via your local QSL bureau to save postage and eventually they arrive at the destination bureau where they are stuck into a self addressed stamped envelope (maybe once a quarter) and delivered to the destination. Radio amateurs in the UK typically send a years worth of envelopes at once, and on 1st February these are all going to become invalid.