JJ's has been getting a lot more crowded at lunch time, so haven't been as much recently. However, I did try the dobradinha again and AT had it once where they made it with red beans. I checked with them and they said only for the feijoada (which is comon for feijoada a transmontana along with white beans), dobradinha is definitely white beans although the broth gets a red tint from the linguica and tomato. So must have been a one time thing.
Dobradinha had nice large pieces of tripe (bucho) still a bit chewy, slices of linguica which had been cooked down, rind-on-bacon, some hot red pepper slices, and the beans. Broth was a bit thinner than I am used to (no potato like some brazilian versions) and it seemed to me that the beans were cooked separately and added without cooking them together much. Snack bar version from what I remember is thicker and it was more subtle (eg less bacon) than Brazilian versions. Missed having nice Brazilian peppers to eat with it.
I also enjoyed their bife a portuguesa much more on a recent visit than in the past. Good beef dripping taste, nice tang (a while back it was reminding me of gravy magic w/o much beef taste). Not quite as good as Terra Nostra which did it very similar, but spicier (the highlight of a mostly so-so recent meal).