On the IITH site a new message is being shown:
Candidates who have chosen ‘Retain and Wait’ under “IIT Hyderabad” on COAP 2018, will be considered in the next Round of offers. Hence, candidates must visit COAP 2018 and make decision on available offer(s) in the next Round. The schedule of time window for the next Round of offers is displayed on COAP 2018.
So I think they have made some offers in the first round of COAP.