I don't think I need to mention it, but shaving ATG is a sure
way of getting razor bumps if your face is susceptible. On
the neck in particular, many gents might be shaving ATG un-
intentionally, since the grain of the beard can be in many
different directions.

To answer your original question, probably a couple of days
is all the time they'll need to sort themselves out. After that,
shave away!

- Scott