Swift Says 100R Distribution Planned For 2025

So will we all need an STC to use this new Swift 100 unleaded fuel. If it is a drop in replacement why would it include an STC. I went to Santa Monica Friday and got some Swift 94UL fuel. There was no one there telling me I needed an STC to use it and the pump took my credit card no questions asked and let me fuel my Skyhawk. I have the STC for the Swift 94 fuel by the way, but I wonder why I really even need it. The fuel cost $7.00 per gallon self serve or I could have gone to Adlantic aviation and got 100LL for $8.60 per gallon.
My question is how much additionally will this new product cost me when I am forced to buy it because some people have aircraft that need this more expensive product, which I really don’t need, but probably will be forced to buy it anyway because they say that the 94UL will be removed from sales when the 100 product comes available.
I now hear that the 91UL product currently used in other locations around the world can be used in my airplane without an STC because my airplane’s engine was originally designed to use 91 octane fuel that according to the FAA.