As I wrote, most occurrences are only in the subjects, not in the posts themselves. I think only two occurrences of bLast within the posts were found, both before the last forum upgrade.
Hmm, I will try changing a topic name to include bLast, just for the sake of curiosity. Didn't work. It looks like though that the only "bLast" after the forum upgrade I noticed was actually in a pre-upgrade thread.
Examples of subjects with bLast in it:
here ,
here ,
here ,
and here.