Angelina
The overall problem with @Christine and her mom seems to be, that each is only using the belt to project the own goals onto the other person and neither considers the goals of the actual wearer.
When Christine's mother was the keyholder, she enforced 24/7 complete chastity with no breaks for masturbating, which we can therefore quite safely assume is her "goal" or "standard" for what she considers appropriate.
Now the situation has changed and Christine is in the position of keyholder, but again instead of keeping her mother in complete chastity making sure she has no opportunity to masturbate (which was her mother's standard), Christine is applying her own standard to her mother, which allows for masturbating and only denies her sex with other men.
I think both @Christine and her mother would benefit from not projecting their own wishes onto the other but carefully looking at what values each has demonstrated and then help each other to enforce those values.
For Christine, that would be being belted again but with breaks for self gratification and in return she should keep her mother locked without any chance to touch herself.
