According to the John Knibbs book, the sixth batch BSA's first came out in Feb/March 1907.

And by action tube do you mean top of the cylinder? Im sure they were stamped H the Lincoln and not Lincoln Jeffries Mod.H

If you could provide the serial number it would make things a lot clearer.

A bit odd but you could have a early batch Lincoln jeffries which has had another stock put on at a later date, or it could be a BSA made H the lincoln (but I believe only the early models made by BSA were stamped H the lincoln or Lincoln jeffries pattern).

Or I could just be getting things muddled up. Like I said a serial number will tell us exactly what it is (at least what the trigger block is off. if it is a bitsa)

But still, dont think I have ever seen one stamped Lincoln Jeffries Mod.H so I am a bit confused but very intrigued.