Well, I had to reserve 3 cars in different groups (1x PXAR, 1x XSAR & 1x LCAR) as my travel plans were not finalised until the very last minute. The number of ppl & luggage on the trip is the variable.
I understand they had to manage inventory (still, they had plenty of cars available from that station) but nowhere on their t&c had any info regarding "automatic cancellation" & the timeframe which allowed me to choose what was suitable at the end. I was lucky this time as the remaining booking provided me with a car that is larger than what I need. If it's the other way round then I would have rented with someone else. If the t&c stated clearly the timeframe allowed for me to cancel the unsuitable bookings myself then it would be much better. The other problem was they never sent me any cancellation confirmations via email or by other means. I only found out after logging onto my profile, with the intention of cancelling the surplus reservations (that was at least 2 hours before scheduled pickup time, there was no intention at all not to cancel the remaining bookings before pickup time). If Hertz wants to do what airlines does then they should not allow any overlapping bookings under the same name in the first place.
The other question is how do they decide which of the bookings to cancel & which to remain as confirmed. Roll of a dice? When I was picking up the car, I asked whether it's possible to switch from XSAR to PXAR. The agent found out that no PXARs were ready on the lot for rental. That meant Hertz can't rent that car to others even tho they've released my booking.