So if William Sabey of Colmworth, son of John Sabey was buried at Thurleigh on 1 Nov 1782 where his will mentions no wife & children, he cannot be the William Saby of Bolnhurst who married Sarah Throssel of Thurleigh on 18 Nov 1785 at Thurleigh. So who does this William belong to?
True. This is one of the ends tidied up by the will. This William of the will must have been the son of John of Backnoe House, who also named a minor son James and daughter Sarah Hartop. And again, no mention of a Francis thus confirming that he wasn't from this particular non-conformist family.
William who married Sarah Throssell was the son of the "other" Bolnhurst Sabey family, Joseph & Elizabeth (Hall), baptised in Bolnhurst on 26 Dec 1752 who was buried in Bolnhurst age 75 on 28 Feb 1827
And one of the questions raised by the will is what happened to my 6xg great uncle William baptised at Colmworth on 3 Dec 1721, who could conceivably have been the William buried in Thurleigh in 1782 until you found the will which removed that possibility
And another question which has troubled me for years is who was John of Backnoe house? There were two John Sabeys both born at about the same time - one who started baptising children in Northill in 1739 with wife Jane, and the other who married in Wilden in 1741 and was I assume the John in Backnoe House. Which of these Johns is the one who was baptised in Colmworth in 1716 cannot be determined. Whichever it was, I'm a baptism short!