I think you're confusing plans / stores. The 100/100/100 plan at Target is AT&T, and has been regularly available since it was widely released in around June, 2023.
I realize this might have been hard to see, since it was added to the old FP Walmart T-Mobile exclusive 300/1000/100 free plan thread, but if you want more info about this newer FP Target exclusive AT&T 100/100/100 free plan, start reading at What is this Freedompop item Walmart is Selling? - #209 by JVV.
If anyone has the inkling, maybe it would be good to split that thread, starting with the link I provided, to more clearly separate the Walmart vs Target plans?