Indeed, one aircraft did have both 201 and 301's fitted for a time, and contrary to the blurb I got from BAe years ago, it's clear that some aircraft were re-engined, so I think I've got all that sorted now - finally! I note that in the article you mention the infamous "B.Mk.2A" gets mentioned yet again. That non-existant variant is never gonna lay down and die it seems! I'm looking forward to seeing if any of the new books uncover anything of interest and if they'll perpetuate any of the old myths yet again - I'm sure they will, but then I'm sure I'll probably add a few gaffes of my own in my book - it's not the most reliable of projects when you're relying on hopelessly confused books, dubious magazine features, a manufacturer that is now only interested in airliners, and former staff who have either died, or long-since lost any records of what really happened back in the 'fifties. I'm aiming to base much of my book on personal accounts (to make it a decent read) rather than just churning-out the usual history yet again (it's not as if you can re-invent it). I think the most interesting thing I've discovered so far though is that despite every book and article crediting the Vulcan's delta/flying wing idea to Roy Chadwick, it seems it wasn't actually his brainchild at all! Just goes to show you can never rely on published information I guess!