Check each frame to
ensure that you will be able to get a suitable guide star. If
there are only dim stars available for a particular frame, check for
180 degrees opposite rotation. If there are still only dim stars
available, strongly consider using longer guide exposures.
Ideally you do not want to deviate from the planned mosaic
positions. The more you deviate from the planned positions, the
more difficult imaging the mosaic will be.
If you are self-guiding, I believe the best approach is to increase
your guide exposure until one of the stars in the FOV is suitable to