@UjwalG I respect you sir but you are wrong here we can apply for ipo through UPI during any period of time it can be morning or night but the mandate come from 10 am to 5 pm and Last time to accept the mandate is last day before 5pm.
An applicant can apply ipo at 4:50 also
My self applied bajaj at 4:15 and allotted in that same account
@PLAZA Here in upi we have to use the same bank account but though I don't have much idea about minor account.
If your minor grandson have upi facility then only apply via upi or else Asba will be a better option.