When is the earliest point to apply for a 3 month extension on a 1 year ED single entry visa?

Does the visa holder need to wait 2 months before they can apply for a 3 month extension and a re-entry permit?

Edited June 10, 201115 yr by WhiteCadillac

There is no such visa. You either have a multi entry visa valid for one year (of up to 90 day entries) or a single entry valid for 90 days. To extend you visit Immigration during the last 30 days of that 90 day entry with school paperwork. You can apply for a re-entry permit at any time but it is only valid for your current permitted to stay time.