Change of Status from B2 to F1 and extension

[Vishal2019]

I just filed I-539 for the COS. Now I have to file the same form again to bridge the gap while waiting for the COS approval, But here at part 3, I/We request that my/our current status be extended until (mm/dd/yyyy). What date should be entered? How can I provide the reference or link the already filed I-539 for change of status from B2 to F1 here? And how do I know that when I have to file the I-539 again for the bridge gap and how many times?
I mean every 6 months or every time my SEVIS start date differs?
Thanks in advance.

[Libra_14]

I guess you better move this question to F1 section - high chance there that you will get someone to reply you on this.