A friend of mine sent me a photo of a Wing Tagged Marsh Harrier he saw at Greylake in Late April below is the BTO ringing scheme information on that bird. The bird was wearing ORANGE tags on both wings with the letter KP on them in black:-

Ringing Scheme: London Ring Number: FP19922 Species of bird: Marsh Harrier (Circus aeruginosus)
This bird was ringed by P C Noakes as age nestling, sex male on 09-Jun-2023 14:00:00 at Hardley Flood, Norfolk, UK
OS Map reference TM39 accuracy -, Central co-ordinates 52deg 30min N 1deg 27min E accuracy -.
Colour Marks left wingtag ON(KP)
Colour Marks right wingtag ON(KP)
It was found on 25-Apr-2024 10:00:00 at Greylake, Somerset, UK

Looks like this was the first record of this bird since it was ringed and I know how happy this will make the person who ringed it, a year old and going strong!