Hi, I have a quick question about my parent's B-2 extension/change status. They arrived in the US in last October and their B-2 are set to expire in April. I filed the extension for them in Feb and asked for a 4 month extension. In July, I wrote a letter to USCIS asking for another 2 month extension. USCIS website showed "on July 30, we received your correspondence for Form I-539". The B-2 extension is still pending now. My question is can I file a I-539 to change their status from B-2 to F-1 now? Do I need to file another extension before I file F-1?
Thank you so much for your help!