Does AD-to-ARNG time in grade reset after a break in service?

I was an active duty SSG, with just under 39 months TIG. Then I had a break in service. When joining the National Guard I was told I would need to agree to a rank reduction to SGT, but was told that since I had been a SGT previously for 26 months before promotion to SSG my DOR would be calculated to go back 26 months, and I saw this entered into a database by individuals at MEPS just before signing my contract. This promise was not honored, however, and once I was in my TIG was reset to zero, as though I were a newly minted SGT fresh from the sham shield brigade.

When I switched over from reserves to active duty my DOR was reset to my first day in active duty. I lost a lot of time.

Branch is irrelevant. You should retain your time in grade/DOR unless there was some type of administrative action that would preclude retention. For promotion to O4/Major you'd still be required to be selected and receive Fed Rec. I've known officers that went Army to Air with no problems as far as rank is concerned.

I should clarify: I’m seeking a way to reset my time in grade to become eligible to try out for Special Forces. As an almost-major, I’m pretty useless to a prospective SF unit, but as a newer captain, I’d still have plenty of time to serve on a team. Is there a way to reset my captain clock? Are there waivers that would let me stay a captain long enough to be useful to a Special Forces ARNG unit?

I’m assuming here that ARNG operates in the same “up-or-out” paradigm that the active duty Air Force does. I.e. you’re either getting promoted or separated, but you can’t be a captain for more than 6 years. If that’s not the case, someone please feel free to correct me.