Yep. As mentioned here already, they run 'A shift' which is everyone available (or 'normal' for us non roster people) and 'B shift' Which is a rostered crew for two appliances. 'B shift' usually covers nights, but if the roster cant be covered, I believe it then just reverts to an 'A shift' response.
Its rather easy, I believe. You let it be known when youre available, then there is the chance that you will be rostered on the times/nights you have shown to be available. If rostered, then you are to stay in the area and trun up, when turned out. The roster can be changed, hence you see pages like 'So and so unavailable until B shift' or 'Can someone cover B shift, blah blah'
For further crewing, they can page out further. Please note, I'm not a member of Barker, and there are members who cruise these boards once in a while. Feel free to correct me...
Roster systems can work, and theirs does. It ensures that you have the correctly trained persons on the appliances, and you *know* who is coming. For those that ask 'why bother?' This morning we turned out to a paged as RCR job with 3 crew, none of whom held any rank higher than FF, nor were they qualified RCR operators. Mind you, before you jump on me for that, there were two other brigades responded, MFS were on scene and there were no persons trapped. But still... out of 40 odd 'active' crew...
So, all in all, roster systems atleast allow you to almost guarantee a crew - something that needs to be seriously looked at by brigades with crewing issues.