As mentioned, the national medal is an award for diligent service, not simply a time served medal, which is why it needs to be on application, not automatically given.
The new CFS medal is a service medal...so when you have reached the relevant time, you get the medal, no application etc required.
And this is one of the reasons that brigades should carefully check their membership lists, and avoid having members given 10 year medals, and no one in the brigade knows who they are!!
Pip