66 oz of stabilizer will add 30 ppm of CYA to your 16,500 gallon pool and lower pH by 0.56. It will take 24 to 48 hours for that stabilizer to dissolve. With your new plaster curing your pH is probably rising by .05 - 0.1 per day.
I would lower your pH a bit to 7.6-7.8 with about 12 oz of MA. With a TA of 150 and curing plaster your pH is never going to come close to 7.2. Check your pH daily and keep lowering it when it hits 8.
