回複：my personal experiecnece

He/She can come back
1. no visa is required if his/her purpose is not a H-1b visa seeking (30-day policy)
2. H-1b visa if his/her purpose is h-1b visa seeking
3. AP

Be aware if the trip is visa seeking, if the H-1b visa is denied, he/she will have trouble to come back.

Personally I feel AP is the easiest way.