Many things strike me as incomprehensible. Try this one.

I left home at 9.45 this morning and the postman came to my door at 10 with an item posted in London yesterday. It needed a signature so of course he had to take it away and leave me a card. The card told me that it would be returned to my delivery office. So far so obvious.

On the reverse of the card it said please leave X hours before trying to pick it up. X appeared to be 40. Now the delivery office used to be five hundred yards along the road but it's now further away. Not so far away as would make it seem reasonable that it should take 40 hours for the item to reach it so I decided that it must be a badly scribbled 4 that was really a 1.

I went to the delivery office just before it closed at 7 this evening (not quite 10 hours I know but I thought I'd chance it). To no avail. The item was not available and I was assured that 40 hours was really 40 hours so there was no use coming back before Saturday morning.

If I'd paid 41 pence first class postage it would have been put through my letter box less than 24 hours after it had been posted. But I paid £5.50 for special delivery and so won't get it till about 72 hours after posting.