i havent received study visa yet and classes are starting 1st sep but i can join till 10th sep.
I did my medical on 10th so should i inform CHC ISB about the extension date??? or wait
Keep your hopes alive for the two working days (Mon,Tue) and wait for the first two working days of next week. If no reply then you can ask for extension.
There is still hope of visas in coming two days.