To be honest, they'll be lucky. I have some knowledge of the UK reserve forces, and right now there is a massive attempt to recruit as the government tries to switch its defence manning policy in a very, very short time. Unlike the US and Australia and various other modern forces (which have a much greater proportion of reserve forces), the UK has until very recently has a relatively small reserve forces. It's common in the US and other such for reserve forces to be part of the routine planning and deployment for operations; the UK has only recently been forced to think like this, principally due to the manning issues encountered in the Middle East over the last decade.
Fifteen years ago (maybe even ten years ago, depending on which reserve force one joined), you could join the UK reserve forces and the general feeling was that one could easily go a few decades without being mobilised; now, people are told on joining to expect to be mobilised - it's routine.
The US is a very warlike society, with a significant civilian buy-in to the idea of the armed forces and reserve forces. The UK, whilst as a nation just as busy travelling around the world to meet interesting people and shoot at them, does not have nearly such a civilian buy-in; there are already rumblings that reservists are just less attractive to employers on the grounds that they can be expected to disappear for nine months, and the employer is forced to hold their job open for them. This is clearly a big concern for the government, because they're trying to push the idea that employing a reservist brings advantages. Many employers seem... dubious that losing someone for nine months is worth the less tangible benefits.
Some reserve forces are being asked to increase on the order of 50% in about 5 years; given that in the UK it can take three years (and sometimes more - five years isn't unheard of; I understand that in some nations, reservists might spend several weeks or even months doing all the initial training in a single block; that simply won't work in the UK unless civilian attitude to reservists undergoes a massive change) to take a new reserve recruit and make them deployable (on the "trained strength" as the vernacular goes) this is one hell of a recruitment target.
The network infrastructure reservist branches are still in their infancy; in the British navy reserve, the branch is very, very new. They are still working out just what they're about. The kind of IT professional I anticipate they'll be trying to recruit will almost certainly feel a bit ripped off to be exercising their years of experience (for which, as contractors, they probably charge up to a hundred a day) on initial pay which, as I recall, is around 40 UKP a day, before tax etc. The initial basic training and militarisation can easily take a couple of years anyway, before they even start thinking about branching, so this might be something of a hard sell; "join us, and spend two years slogging around fields in the mud, and eventually we'll use your civilian skills at a much lower rate of pay than you get for them in your day job". Given that one of the main selling points of the reserve forces in the UK is that you get to do something a bit different, this is going to be a very hard sell.
Not that I know of, and I'd be awfully surprised if it was. The UK reserve forces really don't do that sort of thing. Even the very niche skills (neurosurgeons, specialists in obscure dialects, that sort of thing) aren't any kind of civilian under contract; they're in the reserve forces, like everybody else. How else would it work?
They need to be able to mobilise people at very short notice and deploy them anywhere in the world under military discipline for the best part of a year. It's no good if they can just say "Oh, I'm busy next week." (although the number of reservists who effectively do say just that when they get the call is astounding :p ) To fit into the military environment they'll need to have undergone the same basic reservist training as everyone else. Certainly in the naval reserve, it's just another branch, like all the others. If you joined the naval reserve for this, expect to go through the two years or so of navalisation and basic training first, like everybody else. There's also the legal aspect; if you're attacking another nation as part of a military effort, and you're not on the books as an official military combatant, what are you? A mercenary? A terrorist? War criminal? Whatever you are, you don't get the legal recognitions and protections that official armed forces get. As I understand it, part of the justification for not treating properly all those chaps wearing orange boiler suits in Cuba is that they weren't proper official military soldiers; if that's what happens to people who aren't official soldiers, I certainly wouldn't be interested!
I did once see someone recruited specifically for his ability to speak Arabic; he was rushed through as fast as they could and given special dispensation for some courses before being mobilised (took about a year from identifying him to giving him a pit in Baghdad, where he had some mutant officer rank because nobody quite knew what rank he should be) but he was in all legal respects just as much in the armed forces as all the other reservists being mobilised. Given that this information infrastructure operations branch is something the MOD are actually planning properly, they are not planning to have it as what you seem to think; essentially a bunch of phone numbers of civilians to ring and hope they don't mind leaving their life for a year at two weeks' notice.
Their civilian specialist team available for consultations and non-military deployment already exists; GCHQ.
ADDENDUM: All the above is based on my knowledge of how things ARE now, and how they HAVE BEEN in the past. The future is an unknown and hey, maybe the MOD does want a ragtag bunch of IT admin staff to partake in military operations.
Fifteen years ago (maybe even ten years ago, depending on which reserve force one joined), you could join the UK reserve forces and the general feeling was that one could easily go a few decades without being mobilised; now, people are told on joining to expect to be mobilised - it's routine.
The US is a very warlike society, with a significant civilian buy-in to the idea of the armed forces and reserve forces. The UK, whilst as a nation just as busy travelling around the world to meet interesting people and shoot at them, does not have nearly such a civilian buy-in; there are already rumblings that reservists are just less attractive to employers on the grounds that they can be expected to disappear for nine months, and the employer is forced to hold their job open for them. This is clearly a big concern for the government, because they're trying to push the idea that employing a reservist brings advantages. Many employers seem... dubious that losing someone for nine months is worth the less tangible benefits.
Some reserve forces are being asked to increase on the order of 50% in about 5 years; given that in the UK it can take three years (and sometimes more - five years isn't unheard of; I understand that in some nations, reservists might spend several weeks or even months doing all the initial training in a single block; that simply won't work in the UK unless civilian attitude to reservists undergoes a massive change) to take a new reserve recruit and make them deployable (on the "trained strength" as the vernacular goes) this is one hell of a recruitment target.
The network infrastructure reservist branches are still in their infancy; in the British navy reserve, the branch is very, very new. They are still working out just what they're about. The kind of IT professional I anticipate they'll be trying to recruit will almost certainly feel a bit ripped off to be exercising their years of experience (for which, as contractors, they probably charge up to a hundred a day) on initial pay which, as I recall, is around 40 UKP a day, before tax etc. The initial basic training and militarisation can easily take a couple of years anyway, before they even start thinking about branching, so this might be something of a hard sell; "join us, and spend two years slogging around fields in the mud, and eventually we'll use your civilian skills at a much lower rate of pay than you get for them in your day job". Given that one of the main selling points of the reserve forces in the UK is that you get to do something a bit different, this is going to be a very hard sell.