Well Jack in Canada has two nests going at the same time. Did it last year and seems to be going to do it this year too. Somebody else (don't remember the name) but I think it was the nest where RM & T are now is suspected of having two ladies (but I suffer from CRS and could be wrong about that last location).
If it is Archer he is just spreading the genes.
If Dan is right and he probably is it's most likely Lord P back to his Lady P if the tiercel is banded. Poor Mr T better luck next falcon.
But
WHY did you guys think it might be Archer does he have a white feather?