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I initiated the manual regeneration arm earlier today - it cycled through by water draining into the floor. " I hope that you mean that during the cycles, the water softener discharged water through its hose into the floor drain.
http://www.water-softeners-filters.com/how-water-softeners-work If that is not what you meant, say so.
It is normal for the salt to be higher than the brine level. You will probably have to remove most of the salt to see what is going on.
Depending on things, the softener might only refill about 0.25 cubic feet of water into the brine tank. It might be more -- maybe double that or more-- based on the capacity of the softener and some other factors. Figure the area of tank, and you could compute an expected rise. Then make allowances for solid salt displacing some water.
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That said the brine tank does not fill with enough water to cover the salt - it use to " Many people fill the brine tank 1/2 way or more with salt pellets. Maybe you never did. But anyway, if things did change drastically, then you will want to characterize the operation a little more by bringing the salt level down so that you can watch more readily.
You might want to get a softness test, or devise your own with soap. Compare how much liquid soap it takes to get bubbles with your raw water (outside faucet?) vs your softener output. The Hach 5B test is more accurate and numerical, and is medium priced.
