I’m not sure we’ll have mixed units and I agree the last thing we’ll be doing as things stand, is buying more M777A2…
The bjg problem I suspect will be workforce. RAA has to retain it’s M777A2 batteries plus support elements.
It has to introduce a new regiment of SPH, plus support elements. Bty size of SPH will be large too with guns and ammunition vehicles, as well as the usual Battery CP, joint Fires troop, CS etc. Mobile Protected Fires from memory is also re-introducing Weapons Locating Radar capability back into RAA, so troops will need to be established for those units.
It has to introduce a substantially expanded air defence capability within 16ALR.
RAA also now has to introduce 2x Regiments of HIMARS for divisional fires capability and at least 1x Regiment of land based ASM, plus of course support capabilities.
With such a massive introduction of new and expanded capability that corps will be under so much pressure. Historically speaking we’re also likely to chuck in a few Corps / Unit re-organisations into that mix as well, just to add to the ‘mess’.
The pressure they will be under will be immense.
I don't necessarily think the SPH batteries will be that much greater in size than the M777 batteries. More CSS for sure, but the number of vehicles works out similar (cutting a GTV and PMV for the AS9 and AS10 themselves, with ammo and crew carried by each). Still, it is a new and more complex training pipeline.
HIMARS is a big one, a completely new system. Getting help from the US would be key I imagine, perhaps even being radical and trying to get people on courses in the US.
Transitioning from RBS-70 to NASAMS is another large one, we'll have to maintain pipelines for both, while I can see us cannibalising the RBS-70 capability to make sure NASAMS works, despite the range/cost gap between them. StrikeMaster may be able to leverage shared FDC, sensors with NASAMS also, in addition to regular PMV qualifications - they may ease the training burden if it is chosen.
Plus drones, radars, sigs...
Not an easy path ahead...
Still, we get what we pay for. The alternative is giving up on one of these entirelly, and with current concerns/vulnerabilities I don't see one that really can be.
I suspect contractors/allies being directly involved is part of the solution. They already know the systems and can ease the pressure on the School to generate courses. Generating the workforce is another issue however - one which all of Defence is going to be struggling with, unless it becomes more attractive as a career/life.