And a Happy New Year to you two, Monica and Ian as well as all who read this

I'll try and do more on naming patterns but I need to discover any siblings of Janet Vannan. I've found four of their children (cannot find more ): John and the three you posted - all via SP. Incidentally, John Bachop; Andrew Balk; Margaret Bauk and James Baulk

The 'ch' sound as in loch does suggest a reason for the variety of spellings.
Tobias and Janet are my 5 X greats as well. Son John and his wife Margaret Duncanson were my 4 X greats.
I've found just 3 Tobias births in the period 1710 to 1717 - though there was a Thomas.
10th December 1710 son of John Bachop & Helen Henderson
31st October 1712 son of Tobias Bachop & Jean Arthur
3rd December 1714 son of John Bachope & Anna Mortimer
The first was in Clackmannan parish and the other two in Alloa (Clackmannan) parish? How do these differ please?I think I will discount the Janet born 1700. Age 46 at marriage and then 4 children doesn't quite ring true. Marriage at 15 (baptised 1731, possibly not soon after birth] is OK but she married one of three men (in 1746) of 32, 34 or 36. The youngest one perhaps is the best candidate - for now anyway

Regards
Reiver