I thought the design function of the regulator was to protect the battery and electrical components from overvoltage conditions. My understanding is that the regulator cuts in at peak voltage and stays in that condition until the battery level drops to a lower predetermined level.
e.g. Regulator Cuts In @ 14.5v,,,Cuts Out @ 12.5v.......So that during the period between 14.5v and 12.5v the battery and the entire working electrical circuits have time to rest and operate at the lower design average voltage.
If the regulator is not functioning properly and maintaining voltage at/near/above the peak level, you would consider it an oversupply situation for the general health, reliabilty and service life of the battery and the electrical circuit components.
If so, I would be trying to verify the regulator cut in/ cut out function is fully operational across the required voltage drop to the design cut out level, before it actually switches charging current back to the battery