NEVER, never spend more than $1 over the min spend required.If you intend to take it up, let's see what you get thereafter.
I got the four week one 6 weeks ago and max I've spent each week was $69.
After fulfilling the offer, I had:
$100 for 2000 points 3 days later (didn't take up)
$110 for 4400 points 3 days later (took this up)
$110 for 2000 points 3 days later (not taking up).
As you get close to the $$ then manage it to be as close to the min amount. Not a competition but better half has got the exact amount (including weighed F&V) 6 confirmed times vs only 4 by me
If you don't have others in household with FB account, then put the other amount through as a separate order without using FBs. Missing out on a few points makes a big difference in future offers trying to get you to increase your spend.
Best approach though is not to get onto that treadmill.