I can't think of any possible excuses that the AFPRB could use to reduce pay in the lower ranks, especially with all that the Govt are doing at the moment to raise the pay of the lowest of the low!
POSSIBLY Off Topic
The Regt. have (quite rightly) re-introduced LanceJack for their guys who have leadership responsibilities out in the play-pen, maybe the rest of the RAF should look at taking it back on too! It would be useful for SACs going into theatre in their early years (without giving them the burden of a Cpl's supposed responsibility) and it would help to even out the whole '3 years and you're up' scenario. The same goes for WO2 (awaiting a sound verbal/typed thrashing from those who supposedly know better...!)
Off Topic
To be honest, I don't think an OpAIC grad would get sent straight to theatre, unless there as part of the new FP posts, but even then they are LACs for a good reason - they've only been 'in' about 10 minutes! By all means, make their Phase 2 more substantial (it used to be a year long FFS) and pass them out as SACs. There was a marked difference in maturity and mental attitude between those passed out as SACs and those at JT, the gap is even more obvious between SACs and OpAIC LACs (IMHO)!!
As for the merger, our guys aren't taught anywhere near what the Int Corps are with regard to security, so the whole training regime for our trade and theirs would need to be squared away before anying like a merger could occur. INHO, a highly unlikely scenario for many years to come.