Mine must've missed the cutoff by days. Came with the HW2.5 computer originally. Build sticker says 4/2019, and I picked it up on 4/19/19. I've had the HW3 retrofit completed so all is good but talk about missing it by *that* much!
OP as @Knightshade said, basically if you are looking at a NEW model 3, yes you will have the current FSD computer. If you are looking at a used one, in order to guarantee you have it (without FSD purchase) then you would need to ensure you had a 2020.
Tesla announced that "all new vehicles would get the self driving computer" in april as was already said but there are plenty of people who took delivery of cars after that, that didnt purchase FSD and still got HW 2.5. If you are going to buy FSD it doesnt matter because they will upgrade you, If not, buy a 2020+ if you want to ensure you get the FSD computer and are not buying FSD.