It was some years ago now (about 2007) when I found a singing male Whinchat and a female near Stileway between Meare and Glastonbury. Not impossible for them to breed locally.
Carried out a late visit to my new BBS square north of Shepton Mallet this morning and came across a female/juvenile Whinchat perched on electricity lines just to the west of the busy A37 near Stomacher Farm, not ideal habitat. Nearest breeding that I’m aware of is on Salisbury Plain. BBS rules are to exclude juveniles from count, this looked like a very smart female and it seems early for a 1st brood juvenile to have dispersed so far, so think I will include it in my count.