Lost post

I have learnt, the hard way, to always put a sender's address on the back of my letters. :-(
I sent a pack of seven illustrations in the post, end of January but as I wasn't near a post office, I weighed it, put on more stamps than I needed and stuck it in a post-box. Unfortunately, Royal mail stopped recognising that address for 3 weeks for some strange reason, (having delivered letters there for the last 8 years), which means everything got re-directed to Belfast sorting office! They pretend to look for it, but meanwhile, you get a curt letter saying you can't claim any money off them without proof of postage. I don't want money, I want my artwork! I'm reluctantly facing up to having to re-do them and luckily they were ink and wash drawings and not full paint jobs.
I'd become complacent after years of problem-free posting but it reminds me of a letter I once received, 6 months late. It was a blackened, smudged offering in a plastic bag with an accompanying letter from the Royal Mail saying 'we apologise for the condition of this letter. The mail collection van caught fire...'.