It appears that CircleK has purchased many Shell stations in the Midwest. I have used Shell 93 octane for at least the last 8 years in my 2004 S4, 6mt, JHM 93 tune Avant. Do we know about the quality of the ensuing product?
I don’t know about your neck of the woods but most gas stations usually get the fuel from the same refinery. Different stations or companies get different additives added.
Given the small wiggle room on actual octane and other claims from fueling stations. I would think you should be good. Also keep in mind that the JHM tune is quite adaptive. As always you can always do a knock check and see if the voltages have gone up with the different fuel but that can also be an issue given the fact that we would most likely be under a winter blend.