Hi meatloaf,
It sounds like your problem has been resolved, so I hope you don't mind me possibly "hijacking" for other people who might read the message.
My TA has also been rising over the past month or so, which had me really stumped since nothing other than bleach has been added during this time. I finally tracked it down to the fact that we've had very dry air and high evaporation rates during that time. I've lost almost 10% of my volume to evaporation in 4-6 weeks! My fill water has a TA of 130 ppm as compared to 70 ppm for my pool prior to this weather. Doing the math it turns out that the TA increase I'm seeing is very nearly accounted for by replacing the evaporation loss with fill water.
Again, this doesn't have much to do with you, but I thought someone else seeing a TA increase might run across this thread and benefit from hearing this, too. Hope you don't mind me horning in. I'll hush now.
Cheers, Gary