Z-shaped bread

Hi. I moved about a year ago, and I felt like I went from an expert home baker, to an awful baker. Here's what changed:- San Francisco (dry, cold, 0 elevation) to the suburbs of Boston (usually humid, extreme temperatures, ~300 feet elevation)- GE Profile electric oven to a GE Monogram built-in electric oven Other than that, not much. And to me, I would think those changes don't matter, but I list them in case someone thinks otherwise. Attached is a recent problematic example of a baking failure. I used the goldtouch williams-sonoma pan, and out came pretty good bread (it's Hokkaido milk bread if that matters). I used the aluminized steel pan, shown here:https://www.amazon.com/gp/product/B004DDNDUY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 (Both were the same dough, made the same way, in an oven on Bake (not w/ convection on), and cooked at the same time for the same length of time. I also used a thermometer on each and ensured both had an internal temp of >190F.) With a cover. It was a failure. See the "Z" shaped bread. What went wrong? (On a side note, I like the idea of the longer pan w/ a cover, because then there isn't a top-crust. However, the bread came out Z-shaped, which is pretty problematic for obvious reasons.) Help. Thank you!