I'm currently on a post graduate work permit and applying for an open work permit (with my spousal sponsorship). On the documents checklist for open work permit, it says that I need an Offer of employment as my permit is LMIA exempt. But I've already been working for my employer for a year without receiving an offer of employment. Do I need to get my employer to go through the employment portal for my application? Should they have done that before they employed me?