Article 1 (2)(11) defines ‘cabin crew member’ as follows:
(11) “Cabin crew member” means an appropriately qualified crew member, other than a flight crew or technical crew member, who is assigned by an operator to perform duties related to the safety of passengers and flight during operations;
To fulfil this definition the company may have to stand the pilots down as "pilots" and redefine them as "cabin crew" A SCCM can be anyone the company deems fit to be so with the appropriate training, for instance, if the SCCM becomes incapacitated the Commander would elect whom would do the task of SCCM , may not be the next most senior member, but whomever the Commander feels can do the role.
I remember when BA hold pool newbies were working as cabin crew, but quite how long horn skippers from IcelandAir will fair!