If Lamptey has fully recovered from injury then we don't need another right back ( we still need 8 [ non U21 squad ] defenders in total of course ).
We await good evidence that the Lamptey of old is back.
I think the situation for Right Back is Lamptey OUT + replacement IN.
It may well be that for Left Back the reserve to Estupinan is a combination of Milner and U21 Imari Samuels.
Yes.
We need 8 defenders in total anyway. Maybe Milner counts as 1 of the 8 - at a push.
And Lamptey could leave. Karbownik probably will go also.
2 defenders needed I reckon - and 1 of those will be a RB.