New EP application during card registration stage

Heyy guys!

I am in bit of a situation related to employment pass and changing companies. Similar to this thread.
Hoping I will get some answers and suggestions on how to proceed after the below sequence of events:

1) Interviewing with company A and Company B
2) Company B is bigger(around 3500employees) and stable than company A(start-up, around 100employees)
3) Company A offered a role(~5.5k) and provided me with tight deadlines to accept.
4) Company B had a long process pending still and i was not sure if company B is actually going to offer me one in the coming days.
5) Accepted company A's offer and EP application got approved in few weeks.
6) Joined company A and they provided me with an issuance of EP card/notification letter from MoM which states to make an appointment for card registration by this date.
7) company B comes with an offer now    which is far better (8k + bonus)

Note: eponline status shows the status as "issued" even though I don't have a card!

Now,
1) Can company B apply for EP application in this state? Or wait for EP card to arrive?
2) Can company B apply for EP application before I resign from company A and cancel existing EP.
3) Will MoM reject the new EP as I have spent like a week in the current company? Will salary bump help in approval rate?
4) In the worst-case i.e. new EP rejected and existing EP is canceled by company A, will I be given some time to stay back and apply for other passes like LTVP etc, what's the process here?

Hoping to get some amazing responses and help!