My H1B expires on 6/30/09 and so does my son's as he is on H4. he is 18 yo. My new H1b has been filed for cap H1B so it will start from 10/01/09.
I have a gap of 90 days in between.
I am working on getting a job during this period probably will be able to get early next week.

But to maintain the status of my son I am planning to file F1 on 6/29/09. Will it be difficult to withdraw the F1 to bring him back to h4 if I get offer and apply for h1b.

Will it be possible to apply for H4 while F1 application will already be in or we will have to withdraw F1 as my preference is to keep him on my H1B and file for GC later.