I agree with Izaquilter. I don't think how you thread your needle has anything to do with your timing going out. If you thread the needle with foot down, the tension discs are engaged, foot up the tension discs are released. It would take more than that to get your timing out. Years ago I had a New Home and I sewed 3 fish houses made out of canvas for my husband and BIL. Fighting with canvas which is extremely heavy and that is what got my timing out of whack. I was young and stupid then. I got a new Bernina and did not let my husband talk me into anything like that again. I think you need a new Bernina dealer and this one should be reported to the Better Business Bureau.
Marilyn