Gosh, we really are in the same boat -- I too included details about the research I'd done on moving our dog in our application, down to providing a copy of the receipt for his new carrier!
The suggestions you've already gotten from @KristenTH are great (including taking a moment to search these forums, as this is not an uncommon request). I would add that if you didn't previously provide screenshots of the sponsor's conversations with friends and family referring to the move, I would add that now. If you know definitely when you are going to move (and especially if the PA is from a visa-exempt country), you could also buy your plane tickets now. You could also include quotes for health insurance, as PA (I take it that's you?) will not be eligible for provincial health care for the first three months, but that won't really go to proving the sponsor specifically will be returning.
As someone who is also applying from abroad, I would advise in general to think through every single element of your move in detail and don't underestimate the benefits of explicitly laying out your plan for the officer. When we sent in our application I actually wrote up a 3-page Word document that systematically laid out our logic and plans, and then attached whatever documentation I could think of to bolster my claims. At the end of the day, the officer is just looking to see that you have thought things through and have a plan that seems realistic and reasonable. (That said, we haven't been approved yet ourselves, so that's just what I've gathered from obsessive online research!
)Also, I've read in quite a few threads that they always state "final reminder" even though it's the first and only one.
