Let's not forget that a new ISO each month will require more disk space on server!
Differences behind these "Update Packs" and Caldron can be that MUP will be secure and tested regular updates, and Caldron not, right? So, if MUP will be adopted, I suggest put ISOs on server by two months, after this they will be deleted. Of curse, if local communities assume this work, disk space will not be a issue and Mageia will can put in its website a disclaimer that they're not responsable by that 3rd party ISOS and recommend official ISOS for production environment.
