i think rspca might back u up here as the birds do need someone on hand to look after them, if you say you are willing to live there and look after them untill the outcome is known, it would be expencive to get someone in and take care of them and it would be unfair on the birds to move them due to thier age,thay shoud be left to live out the time thay have in the loft as your grandad wanted