Your link to Classes in the wiki is broken:
https://tech.lds.org/wiki/index.php/Classes
A few points about class rolls that might help those who are trying to manage class rolls that are not 'standard'.
If you have more than one class with the same rules, when you cross a date boundary that changes class membership (it also applies to new move-ins) all of the individuals will be applied to every class where the rules apply to that individual.
For example, if you have your first meetings on Sunday, January 2nd, and the primary wants to have two Valiant 9 classes next year, and keep the same kids that were in the two Valiant 8 classes for the prior year, when you try to create the classes and print the rolls the week before (prior to January 1st) it doesn't work properly. The MLS software doesn't have any way of knowing (or specifying) which of the two Valiant 9 classes each child should end up in, so it puts each child in both classes. Currently the only and best workaround for this (of which I am aware) is to wait to designate the individuals to the proper classes and print the rolls for the primary (or Sunday School) until January 1st or later. This may be an inconvenience, but it correctly addresses the challenge of the current design.
If you have more than one class with the same rules (the above example, or Gospel Doctrine/ Gospel Essentials is another good one) then any new members of the ward get put into every class where they could be... meaning that they will show up on the rolls for both Gospel Doctrine and Gospel Essentials by default.
Some ideas to consider, if they haven't already been considered (and admittedly they may go down on the priority list, compared to other items) would be to have the ability to designate a default class, when all other rules are equal, or to make it possible to designate the destination class prior to the date boundary for change. Another possibility would be to make it possible to carry forth two classes to the next age group, intact. I can't really imagine this would be programmatically simpler than being able to pre-designate the class or just asking the clerks to explain to the Primary President or Secretary that they will have to get those done right before church on the first Sunday of the year. Having a default class (or a class balance algorithm, but I'm not sure that's the best approach in THIS church
) for the individual to fall into, instead of the others, would take care of the issue of having new members show up on each class roll and having to do extra work to maintain those each quarter, by removing the members from the extra classes that they are not really attending. *Edit: The section in the Wiki (link above) about classes adresses this 'default' class issue partially under the section 'Specialty Classes'. Anyone trying to tackle this issue would be well advised to read that section.
Just something to consider.
Oh, and the leadership tools online allow class attendance rolls to be printed out from the web for those who have such permissions, but they don't currently reflect classes that have been split in MLS. I don't know if this is by design, failure to implement yet, or omission, but I'll bring it up here, just to get it out there.