Lots of these flying around the same wall that is still occupied by the Andrena carantonica bees that I posted a couple of weeks ago.
No interactions present.
A quick google for Nomada flava (as I still didn't know whether it was a bee or a wasp!) Aha! I did wonder whether it might be a cuckoo bee, as they were all flying around together (but my husband was sure it was a wasp). I win - he he!
Thanks for the help.
Wespbienen in German.... but you are right though ;-)
Lat/Lng: 52.1, -1.6
OS grid ref: SP3351