Can't answer the VFR question
In answer to your other queries...recruitment is an ongoing process...however your location on PPRUNE says "UK"....so it depends on whether or not you are a Canadian citizen or a UK citizen. If you are a UK controller...then unfortunately you won't get very far with any application at present.
You are posted where you are needed. You can express a preference but it is the companies discression as to where they send you. IFR will always be the majority in terms of need...but if they are VFR short at the time...you will get posted VFR.
If you complete a training course and then on job training it means you are already at the unit..and have qualified as an ATCO so it means there is a job with you for as long as you want it. NAV Canada won't turn round and say "sorry we don't need you" They only do that if you are applying from the UK.
Pros and Cons listed on previous threads. I think it would help if you identified your circumstances first as it really will be tough for you if you are from the UK and not a canadian citizen. NATS would be your port of call if you are a Brit.