Since the BHX-BHX flights appear to be going on sale publicly on the Biman website as some sort of quasi-scheduled or scheduled charter flights...as daft as it may sound, I assume formally speaking Biman must apply for domestic cabotage traffic rights from the UK DfT, which also requires non-objection from UK carriers?
I'm not saying that I don't want to see hear flights operate (quite the opposite) but one wonders whether the DfT would require traffic permits requirements to be followed to the letter (remember the Thai Business Air debacle in LBA?!)