There's lots of 'gag appearances' in LOTSW, such as Stan Laurel's daughter, Jim Bowen, John Cleese.
I don't know if Roy intended that these celebrities should be included - it could be more likely that Alan JW Bell brought these people in.
We do see Ivy at home again - preparing for Compo's funeral in Just a Small Funeral.
In Small Tune on a Penny Wassail, I don't think Clegg was actually living at the location near the church/cafe.
The continuity of where locations are...