Melchy, my view is based on the political situation. Generally, there are few votes in Defence spending (until it gets too late!) and, at the present time, increasing spending on other domestic issues is becoming important to maintain enough popular support for the Tories. Therefore, I judge that Defence spending will take a hit in the near future. Spreadsheet Phil will bank on that (but not say) in his calculations for the Budget. The Defence cuts will have to be limited to keep to about 2% GNP. As far as the 1% Public pay limit, I see that falling to the wayside in stages.
Opposition to Defence spending cuts from the Service chiefs will be tempered by the (political) Defence review and, the hard fact that, if the VSOs don't like it, they would be dealing with far worse cuts if Corbyn and co get enough popular support.
Just the way I see it.
