This happens to me as well, but it's been happening since before B&H, I'm positive. It's been happening basically since I built a greenhouse (yes, that door is closer to the "front"), which was well before B&H came out.
And then, after I flipped the house so that the front door is technically in the back, it would regularly reset to the house's back door but the lot's front door. (my family is on the big lot in Windenburg, which has a whole slew of issues, so I flipped the house to hopefully get sims visiting to be knocking on the door sooner considering they already are walking forever from where they generate).
However, today, it set the greenhouse door as the front door for the first time in a little while. Which is weird, based on the comments above and the trends I had been seeing, because that door is technically the furthest "back" based on the lot's settings.