ASW get hundreds of CV's a month. Why would they reply unless to say you have an interview?
To answer the question about the mighty dash, it is a modern all singing, all dancing EFIS machine with a FMC, TCAS and all the modern toys (I think it was designed buy boeing who owned DHC at the time. It is not a Q300, there are no q300's on the uk reg that i know of, they are dash 8 311a's.
There is no set roster pattern, you can request an unlimited amount of days of each month, and 9 times out of 10 will get them. Hours can be anywhere between 50 and 100 hours a month.