Common (or Spotted) Sandpiper - London UK (1 Viewer)

Saw this bird distantly at the back end of last year and wondered if it might be better than Common Sandpiper but talked myself out of it, saw it again today but closer (and then saw a definite Common Sandpiper later) and have a bit of a niggling worry that I might be throwing away a Spotted Sandpiper.

I tweeted a photo and had a comment about the possibility of it being Spotted, which made me worry more!.

Looks to have a bi-coloured bill, yellow legs, pot-bellied, possibly feinter wing bar in flight, no notching on tertials (not sure thats significant), maybe slightly paler than CS and a seemingly shorter tail.

Apologies for fuzzy photos, distant, poor light yada yada yada.

What do the panel think?

Last photos, thats all I have.

Sorry BH, can't see this as a Spot Sand? Tip to tail ratio fits Com Sand. Legs and other deets? Obviously better photos would give more useful info. But on this selection? Struggling to see a Spot Sand here. Better photos would help and shot of open wing. Until then, Com Sand for me... (But of course I may be wrong. )