I believe the $300M is the direct pay and O&M cost; imputed costs (base support, uniforms, ammunition, accruals of capital assets etc) make up the balance of the $1.2B.
Land Force Reserve Restructure was supposed to impose a rational C2 structure on the Army Reserve (among other things). Imagine an Army Reserve that acknowledged and embraced geographically dispersed units, and, within the current 20K(ish) cap, provided 30 battalions of 500 trained soldiers each, organized into five brigades of 3200 each (giving six battalions each - two inf, one recce, one arty, one engr and one CSS, plus a Bde HQ and Sigs, plus a few other enablers), plus a training system of ~36500 - that's 80 trained pers to manage and train the BTL plus 650 on the BTL, for each Bde, plus 350 for Advanced training (year-long courses) and levels above Brigade.
But instead, we must preserve the status quo of LCols commanding 90 soldiers, all ranks, including 25 untrained...