<human>: Hopefully someone can give me a hand.

I am originally from the US living and working in Canada. I have been employed by the same employer for 4 years, but am currently working on a closed work permit (employer, position, salary and term). 

There have been some changes on the management on top of me, and my spidey sense tells me I might be forced out. My problem is, if I am terminated, I cannot legally work for any other company in Canada until a new permit comes through (3-6 months).

In my application for my permit, my old boss signed a letter stating that they would employ me at x position for y salary for a term of one calender year. I still have 8 months remaining. 

If they were to terminate me without a reason (99% of company employees are 'at-will') would they have to pay out the remainder of my work permit/contract? To clarify, on top of the letter to the HRSDC no other contract in place.

On what grounds could they legally terminate me? When could I push back? I have no problem getting a lawyer involved when the time is right, just that all I have spoken to will not offer a consult without a retainer and a min. billing period.

Can you give me the gist of the text in a nutshell?
<bot>: Company sent government a letter saying they would employ me for a year, they might change their mind, no performance reasons to legitimately fire me, can I sue for the remainder of my work permit?