I will have a roughly ~7 hour layover between my international arrival and domestic departure at BOM in a few days. Factoring in immigration/customs/baggage re-check and then departure security check that leaves perhaps 3-4 hours. Given risk of delays, I'm not going to book in advance, so my question is, how common is it to be able to get a room for ~4 hours as a walk-up at the landside location? Or is it perpetually full that a reservation is required?