BlindSquare stops tracking a place before I have arrived. How can I prevent this?

Just start tracking the place again.

BlindSquare will not turn off tracking if tracking is started in the vicinity of a place. If the place you have been tracking was a Foursquare venue, you can also reset its location. This will cause BlindSquare to consider the new position you have saved as the destination, when you track the same venue the next time.

To do this, open the venue’s Place Summary screen and double-tap the Set Correct Location button.