Generally they will hire around 4 pilots per course, which is historically every 3 months. I would not hold your breath for a large number of direct entry Dash FO positions, just one or two here or there to satisfy succession planning requirements. Even then you would need some serious multi command or turbine experience to be considered.
They seem to hire primarily Bongo pilots with a relatively quick progression onto the Dash or F406, depending of course on movement within the company together with your bidding preferences.
Whilst i am no authority on the matter i would expect that there will be dribs and drabs hired for Dash and F406 but primarily Bongo drivers. Also, with the new contract in the wind there will be no Bongo or F406 as of July 2007, meaning that all of those already within the company will be offered an opportunity to upgrade onto the aircraft being used on the next contract (rumours all around about what the type would be but you would have to guess Dash 300's).
Certainly wouldn't be a bad company to be associated with in terms of progression. Heard they are great operators to work for.
Fly safe.
Ratter