At T1, B is "subjectively true" (I believe that B). However it's not an established truth. From the point of view of the whole society, the result needs replication: what if I was deceiving everyone? At T2, B is controversial. At T3, B is false.

Now is the status of B changing over time? That's a good question. I would say that the status of B is contextual. B was true at T1 to the extent of the actions I had performed at that time. It was "weakly true" because I had not checked every flaws in my instruments. It became false in the context of T3. Similarly, one could say that Newtonian physics is true in the context of slow speeds and weak energies.