As far as I know, M1A1 AIM and M1A2 SEPv2 would be on the ~520mm KE range (at very least using the first improved armor package designed on the late 1990s), and M1A2 SEPv3 would be on the ~600mm KE range (new, further improved package developed on the 2010s).
But knowing Gaijin, they will keep every Abrams with the 1979 M1 hull until SEPv3; and will give SEPv3 the raw package designed on the 1990s (500mm KE).
To be honest, I have no idea why SEPv3 isn’t in the game yet.
We can get Leopard 2A7V, we can get Leopard 2A7HU, we can get THREE STRV 122S… but we can’t get a single properly armored Abrams.
You bought Alkhalid? Trying to grind Chinese is a bit… Anyway I am done with it, but Chinese ground without CAS is painful. I need to buy like 1k GE so I could unlock more spots, 5 is a bit short for GRB RN.