19:57:01 +/- 10 sec for me. Yours won't be very far away from that, and will be earlier if anything but by no more that 20 seconds. It is always worth checking a minute or two around the prediction, but don't go too far.
http://www.asteroidoccultation.com/2..._18539_Map.gif
I wouldn't know how acurate Sky 6 is for predictions, but the data presented by OW has come from the uber-gurus.