They will need the DCPC from Monday next week!! Simples. That is when "eventually" starts.
There's more info on this in the current edition of RouteOne which you can find online.
http://www.route-one.net/issues/503/index.html#/2/The other exemption mentioned is "where driving is not the person's main job", such as mechanics, farmers and a few others. It could be suggested that "teachers" jobs do not include driving as their main job, but if teachers are specifically trained to drive minibuses, then driving IS part of their job.
As for whether passengers pay to travel, that again is immaterial for the cases I mentioned above. The Glockner definition is whether the operation is for "financial activity" regardless of the status of the operator. It also matters not whether the driver is paid or voluntary. In my view the safety of the passengers and other road users must come first and the longer UKplc buggers about trying to find loopholes in the law, the more danger our minibus users are in.
The same argument is made for volunteer hospital cars. why should they be exempt from ph/taxi regs when they are basically doing the same job as us? Does anyone ask THEM for a CRB check? Medical? H&R insurance?