My transactions followed the T&C's: all over $35.00 and always "pay at the pump."

I decided to go for all 6 cause I did a few initially and was super surprised that they posted (the 1st thru 4th transactions) and thought "oh citi merchants must be super reliable now " and then did the 5th and 6th.
And...well the 6th one failed me.

There was also a promo with Circle K where if you signed up for their rewards program first 5 fill ups were $0.20 off/gallon up to a certain amount of gallons (I forgot) so it was worth the chance to experiment. (mind you this was during Chase Freedom 5% on gas rotating category time - so I chose to do this instead of Chase)