Another block should work, and it might build on the effects of this one.

I've had blocks that worked for a few hours and I've had blocks that have lasted for over a year (in an area of spread).

The technique of the doc can make a big difference, but not everyone reacts the same and it's impossible to predict.

I think it's bad advice to push your activity to the point where you'd normally cause a flare. That's never worked for me.