Generally, they get credited alongwith the statement and are reflected appropriately. However, I would double check the spend eligibility of the transactions to see even if they are eligible for reward points.
Been a long time hdfc credit card holder and never suffered such issues. But you have to be watchful.
Once it happened that I used reward points and card spends to book a flight ticket. I was using an hdfc airmiles card then. Due to technical issues the ticket booking failed. The card spends were credited but the points were not credited back to my card account.
I had to follow up with the credit card helpdesk a couple of times. Believe me, it is always a good bunch of idiots sitting in the first line of customer care. Anyways, being persistent enough I got them back but after much hassle.
Thank you.