I don't know what these birds were. At first I thought they were swallows, but they had white under their wing tips rather than close to the body (and under the body) and went round and round in very large circles in the sky. Swifts? Martins? Don't know. They went higher and higher up.
yeah maybe there were some welcome swallows in there too. But some of them weren't and looked very odd. I'll have to try and get better photos next time.