^ yep, I had to do this when I special ordered a jacket a few years ago - I went up 2 sizes from my usual 40L to 44L (I have see some 40L jackets from other makers that are up to 19" in the shoulders, but most of my others are around the 18.25" range). I actually ordered 2 jackets, one of which I ended up selling because I was never 100% happy with the fit, and I still have the other one. Unfortunately, it's a heavy Harris Tweed jacket and I live in Florida now, so I hardly ever get to wear it
In retrospect, I wish I only sized up from 40L to 42L, that probably would have worked out better for me. I really see some fabrics I like in the new Factory Finds, but unfortunately I have zero disposable income to spend at the moment, which is a shame because there's at least one or two I'd really like to have.
+1, I think that I even got the same jacket that you did in 44L due to the shoulder measure, but with that I had bought a 42L. I was lucky enough to get to the store last month and it's clear that the 42L will be the right fit for me. FWIW, I'm a 41L or 42L in BB Fitz, 42L in BB Milano, 40L in BB Regent.