I've bought the Aegean pass for ATH-ZRH with bookings up to 0-days in advance, and at first I struggled to find a flight departing in the next 3-4 days. Aegean Pass didn't show any available flights, while at the same time there were flights being sold at their website. For flights during xmas, to my surprise, I also found out that not all flights are available to be bought with the Aegean pass. I've ended up booking my flights with the pass even 30 days in advance, and effectively the 0 day in advance pass goes to waste. This is actually very frustrating, because you don't have access to "busy flights" or more generally flights on dates that would actually make sense to use the pass for (24 Dec for example). I find this to be misleading from Aegean's side, as this wasn't mentioned anywhere (please correct me if I'm wrong). Has anyone else noticed that? What was your experience?

I also confirmed this with a friend who was the ATH-LHR 7-day pass. Availability was limited.