Increasing your TA will also put support for pH to rise. With new plaster and start up guidelines, I understand the desire to raise TA to 80 but let if find its own equilibriu. 60- 80 is your target. My TA has settled out at 70 and keeps my pH fairly stable. Maintain pH in 7.6 area so you do not keep lowering TA with big doses of MA. If you have not read the following article, this may help guide you
www.troublefreepool.com
Have you added stabilizer. Thanks for linking your PM logs but I do not see any data in it.