Roasted some more last night (Wholebean Premium again), this time properly (i.e. didn't over-extend the roast by leaving the filter out!). The roast was about two and a half minutes shorter as a result. Took it to first snaps of 2nd.
Will try it in a day or so and let you know what I think this time. I presume you guys got my mail about the first batch? No-one replied.