Capital gains tax

I bought an apartment in Pune in November 2023 (Agreement to Sale was registered in November 2023). The building is under construction and the expected date of delivery (OC, CC) is between Oct-Dec 2024 (when the builder expects to provide occupancy certificate and completion certificate). I bought this apartment through a loan. I would like to clear the loan, I have another apartment in Bengaluru. I bought it in May 2013. I was planning to sell the Bengaluru apartment and clear my loan for the Pune apartment. When I bought the Bengaluru flat, the agreement to sale was not registered, but after completion, the sale deed was registered. However, in Pune, the builder said that only the agreement to sale is registered, and then the purchaser only gets OC and CC from the builder. To get an exemption from capital gains tax, I have read that the new property should have been bought before 1 year of the sale of the old property (or two years after the sale). I wanted to ask a) whether the purchase of the new property (in Pune) will be dated November 2023 (when the agreement to sale was registered)  or Dec 2024 (when we expect the OC, CC); b) is there a provision for drafting and registering the sale deed (when we receive OC, CC) and whether that matters for the date of purchase of property calculations (for capital gains tax)? c) For the Bengaluru property, if I have to pay capital gains tax, will that tax be levied only on the difference in value (difference between purchase price in 2011 and sale price in 2024) so that I can use the money to repay the loan even if I have to pay capital gains tax?    Thank you very much for your advice.