Extremely fast fermentation.

[Rookie]

I just did a bitter with Lallemand London ESB yeast that went from 1.040 to 1.012 in about 40 hours.

That's probably not excessive (the attenuation isn't huge so it shouldn't take too long, assuming all is well), though I wouldn't wish it any faster. Obviously, a lot depends on the recipe and the brewing, but hopefully it won't drop too much more before FG.

I am happy with the attenuation, 70% is pretty good compared to some posts I've read about this yeast barely getting more than 60%.
This was an extract no-boil batch.

[Rookie]

I just did a bitter with Lallemand London ESB yeast that went from 1.040 to 1.012 in about 40 hours.

That's probably not excessive (the attenuation isn't huge so it shouldn't take too long, assuming all is well), though I wouldn't wish it any faster. Obviously, a lot depends on the recipe and the brewing, but hopefully it won't drop too much more before FG.

I am happy with the attenuation, 70% is pretty good compared to some posts I've read about this yeast barely getting more than 60%.
This was an extract no-boil batch.

I'm about one third of the way through this batch and after nearly three weeks in the bottle it is quite clear.