Other possible explanations…
Non-Confirmed Features:
• Global Positioning System Upgrade:
The SEP v3 is also expected to get a more advanced force-tracking system which uses GPS technology to rapidly update digital moving map displays with icons showing friendly and enemy force positions, currently a pair of new antennas have been seen being fitted and tested on some older SEP v2 tanks. (Note a PAIR of new antennas and that photo shows a PAIR).
• Joint Tactical Radio System: Integration of the Government Furnished Equipment Joint Tactical Radio System Handheld, Manpack, and Small Form Fit radio to support the need to establish network readiness and maintain battle command and communications interoperability with future Brigade Combat Teams.
https://m.facebook.com/media/set/?vanity=AllAboutM1Abrams&set=a.1495621837151067
So maybe it is GPS and has nothing to do with ammo and range target practice. My Avatar is of a M1A2SEPv3 and it doesn’t have this antenna. The photo below is 2020 and as you can see, it lacks the beefy frontal bow tow hooks–and the new PAIR antennas.
