I’m no expert but In your case a little stress might be needed. As far as the the actual cal mag, I really should have asked what your medium is and what kind of water you use…
If growing in soil and/or using tap water, there’s likely a fair amount of cal and mag already in there. I really try to titrate down the nutes as the flowering period goes on. Having the plant stress and cannibalize itself is not necessarily a bad thing…..it wants to to finish so try sending signals that it will receive and try its best to do so. Eliminating anything that’s already present lessens the chance of excess nutes causing u problems.
I’ve never experienced or read about plants re-vegging, but it looks like she may be doing just that. U might seek some advice on that topic.
I see a plant that has a solid month to go, so I would reduce the light to 12/12 and let her grow and finish. Feed her but err on the light side and I think she will eventually do her thing and get ripe.