We're users of Ejet from Bristol 3 or 4 times a year. I'm an avid 'watcher' - like to book early for the following year, ideally on 1st day flights are released. I've found the email alerts useless in relation to the scenario i've outlined - the alerts are usually a day or two behind.
I'd expect April-June flights out within next 2 weeks and July to September around mid November.
My tip is to go into Ejet website twice/day from now. Second tip is to look on Flight timetables on Ejet - this usually updates about a day before the actual flights for next year can be booked. Then u know that within next 24 hours or so the actual flights will be bookable.
Hope that makes sense