(1) Doesn't matter. The only thing that matters is what her current status is, and when this status will expire. If she can legally remain in Canada for 6 months, she can stay here for 6 months. Plans can change, and officers know this. As long as she doesn't overstay and goes without status, she is 100% fine.
(2) She will be added to your PR application regardless, either as a spouse or as a common-law partner. There are some additional documents you will have to submit, e.g. marriage certificate, her medical examination etc. and your fiancee will also need to obtain an ECA for her education, take the IELTS/CELPIP test, unless you're not claiming any points for this. But nothing that should delay/complicate your application - especially since you already need to get these things for yourself anyway.