zlacker

Customary (and extremely welcomed by the many postmen & women I've had the pleasure to know, my father having worked for Royal Mail / CWU) in England as well as Scotland (and I'm sure in Wales/NI too - probably elsewhere as well, and even in places where it's not customary it won't do any harm to thank people providing year round services to you with a small gift once a year!)

Also, while I agree with you that in this case (having a full postcode as well as name) it would have likely been an easy task for the local postie, Royal Mail do actually have a small team* of people who work in figuring out more tricky ones, so if a local person can't work it out for being on their beat it can be sent to the "address detectives" (great title!) to try to solve.

This is a great example of that from a year or two ago, including a few other similar stories at the end: https://www.theguardian.com/uk-news/2022/jan/07/lives-across...

* My knowledge is both 20 years out of date and fuzzy in my memory, so I've no clue how big a team it is nor if there's enough confusingly-addressed items to need anyone working on it full time, or if it's just one aspect in a wider set of responsibilities that a team does when needed.