Well party lines are drawn for 6 May, with an SDR to follow later this year.
It does make sense to review the UK's defence spending at this time, the world today is very different to 1998. There is still the spectre of a potential superpower enemy (China), but now the possibility of more minor operations against states such as N.Korea and, more likely Iran - as well as potential operations countering NGO's in places like Somalia and Afghanistan - in addition to the old melting pots that are the Falklands and other potential resource rich areas of the globe.
It is, therefore, hard to see, from the RN's perspective, how much if any of its capability can be cut without it causing damage to UK interests. Naval vessels require a long time to develop and get operational, so cutting the capability of the RN would be foolish, even if such a crisis was to break-out.
Nevertheless, I am sure there will be some way the budget can be cut, or more got out of the current resource allocation.