I just launched the Editor. I see #707 IJA Infantry Squad, with Anti-Armor/Anti-Soft/Load Cost 5/20/17, without any upgrades, but also #709 IJA Infantry Squad with 5/22/19, which upgrades to #710 Infantry Squad, with values 25/20/17.
I started the game and loaded a first-turn save in Tracker, and it tells me there are 18684 #707 squads, and 8130 #709 squads.
However, when checking with the Editor the Scen 007 (Quiet China), which I know I haven’t updated, I indeed see that #710 has an unmodified Anti-Armor value of 5.
Therefore, the difference comes from AndyMac’s update to Scen 1 & 2. I guess you play an unmodified Scen 1.
Good to know, I wish I had that modification in our game.