What should be the reason in written statement for applying H4 to B2 COS?

I have applied for COS H4 to f1 and have biometrics scheduled for this week and the visa is expiring 1st week of May. As a bridge application I was advised to file H4 to B2 cos application as h4 extension is not an option to file.
Is it mandatory to file h4 to b2 while waiting for the other decision and my status is expiring soon?
I am in end of my Second semester, can I continue my studies while waiting for COS after I94 expiry or Should I stop my studies and anything from DSO needs to be updated?
Can we give pending COS application as a reason in the written statement for filing H4 to B2 COS? Or covid situation as a reason for not travelling right away??

Who advised you to file B2 while your F1 is pending?

I was told by Reddy and Neuman Law firm that when they view my COS H4 to F1, If my H4 is expired and there is no other pending H4 extension application or any other application, My COS will be denied. I had also read couple of posts in Avvo regarding this. However it didnt make any sense to have another application when I have timely filed the H4 to F1 but didnt want to take a chance on H4 to F1.