Thanks for finding that post
@bgula, I searched and searched for it last night and just wasn't seeing it.
There is another post by Days in the Sun where she tells us about her original upgrade. There is a breakdown the $ involved. I'll redo the calculation when my brain is awake and thinking clearly.
Edit to add the math:
5 day pre Canadian pre Feb 12 - $362.10
7 day current online - $436.65
5 day Canadian - 271.58 (current as there was no increase)
upgrade pre Canadian ticket (436.65-362.10) = 74.55 they could possibly add $40 gate fee
upgrade Canadian discount (436.65-271.58) = 165.07
1. 165.07x2 + 74.55 = $404.69
2. 404.69 + 3x40 = $524.69
These are worst case scenarios. You might get lucky and get a more favourable amount