Eh, if you're junking the Boardman, just let me know which day is bin day around yours...
I guess it depends on how you like the rest of the bike - if the answer is "not much", or you want the spares, I suppose a new bike makes more sense than a frame swap.
i do like the bike but the bb is just killing the enjoyment of riding it. i was thinking about getting the bb replaced then selling it for a good price. try to get a bit of cash back from it to go towards a possible replacement.