Effective date of change from F2 to H4

[Amarm79]

Hi, 

My H1B is approved on 23-Sep and my COS from F1-H1B started from 10/01, so I'm applying for COS for my family from F2-H4. While filling the I-539 there is section Part 2: 3.b where it says "New status and effective date of change" i.e. from F2-H4, new status anyhow it should be H4 but I have a question here, what should be the effective start date of change, can it be past date as my H1B approval date i.e. 10/01 or something else in future, but if its a future date then on what basis I need to choose the future date? please help me ASAP. 

Thank you in advance...

[User099]

If I reading this correctly, you COS is approved and effective from 10/01. How can they continue to be on F2 if you switched over to H1B on 10/01?

It looks to me as if they might be out of status. Talk to an attorney to make sure everything is good before you file for their COS.