Refused work permit application

Hi,

My employer committed a mistake of applying for my LMO 3 days after they have submitted the application for my work permit extension. As a result I received a letter from the immigration office telling me that they have not received my LMO and I only have until a certain date to submit my LMO or they will process my application without it, which means to say that my work permit will be refused.

My questions are:
1. Until when does my "implied" status end, or until when am I legal to work in Canada?
2. Once I received the letter telling that the work permit application has been refused, do I need to leave Canada immediately?
3. My employer is telling me they can apply for the restoration of my status (but I'm not allowed to work during this time), how long does this take? can they just "re-apply" for the work permit?
4. Now that we're just waiting for the refusal letter from the immigration office, can I already apply for a student visa for example (even if the work permit application is still ongoing) to retain my valid stay here in Canada?