My current XBL sub was due to expire in Feb 1 2020.
Redeemed the 18 months from Costco deal + 3 months for turning recurring payments off/on. 21 months total.
Tried the 1 month PC Game Pass beta for $1 but no-go as I'm in Quebec. Price for me was $5.99 so I skipped it.
To my surprise, I had no problem getting the 3 month GPU for $1. I expected this to be priced at $16.99 being that this promo is generally not available to Quebec. 24 month total now.
Finally, I had a 14-day GPU code from McD Monopoly. This was my back up plan if the 3 month GPU sub was only available to me at $16.99 ... The 14-day GPU code could have converted my XBL sub. A final surprise was redeeming this code triggered another 1 month free for turning on recurring payments. More than made up for missing out on the PC Game Pass month at $1. Final tally at 25.5 months of GPU.
Extended to March 17 2022 now. That's $53.47 before tax for 25.5 months of GPU. Or $2.10 per month. Not too shabby! Also was able to use the $20 off $100+ promo on the Costco purchase but I won't factor that in as I bought another item to reach the threshold and not many people would have been able to get it to apply to the XBL codes.