Whilst seemingly a logical move to take advantage of an available resource, this is actually a damning indictment of the state of manning in the Service. Local Service Airmen (and women) were around way back when I joined the RAF, so the basic principle is not new. The idea is based on people leaving the Service because they want to stay in a particular area (perhaps they have married locally for example), but who still have specialist skills for which the station is in need - I am sure you can think of people in this position? However, the fact that it has come to this is exposes the inadequacy of the offer against the demands of Service Life.
What we are currently seeing is a situation where there are gaps at almost all officer levels up to and including wg cdr. In order to keep a post in existence which Manning is 'unable' to fill, the relevant department has to demonstrate the ongoing need for it, either by buying-in contractor support (and you can imagine what that costs) or creating a temporary Full Commitment FTRS post for, say, 3 years, hoping that the post wins the lottery and can be filled when the 3-years is up. What is deeply unfair is that such posts may be given to people of a lower rank on the basis of a job application rather than as the result of a prom board. So, the chap or chapess who just missed the cut-off for promotion to sqn ldr may be overtaken by someone far lower in the pecking order but who is prepared to leave (or may have left) the Regular RAF for FTRS (FC), under similar terms.
We tend to think of the inability to recruit as impacting at the lower levels only, but in practice, 'Manning' limits promotions at several levels in order to maintain some form of hierarchy. People who, in years gone by, would have moved onwards and upwards are kept where they are because we still need people at that level.
I'd love to see the stats that prove it isn't true!