Taking delivery ITM call option buyer exercise

@siva @Bhuvan suppose with enough funds a options buyer exercised his call option on TCS with ITM. So at 3 30 pm only he will pay the lot size X Strike price and buy the shares?. So next day at 9 am only he can sell right BTST ?

Or T+2 demat sell only allowed?

And What if spot comes down well below strike the very next day? The whole ITM exercise is futile?

Like US or somewhere in between exercise before expiry is not allowed right?

No, it will take T+2 days for the shares to show up in your account, so only on tuesday you can sell.

It can come down or go up, and generally people won’t do physical delivery thinking of BTST considering the high costs involved.

Just wanted to know I can close my position at any time before expiry ie last Thursday of the month before 3:30 or I’ll be forced for physical settlement if I don’t close my position on Tuesday.

You can close before 3.30 on thursday.