ATT internet rate increase and ACP.

I have been getting my internet from Spectrum. Their promotion is over, and the rate is about to go up. It's still not so bad with my ACP discount. I talked to a very nice lady at ATT. Their current cheapest plan with 12-month promotion will save me only $10 a month if I switch from Spectrum.

"What will happen after 12 months?", I asked her. She told me not to worry, "ATT will never increase internet rate for people enrolled in the ACP. It's our policy."

Based on my previous experience with ATT, I am extremely doubtful about anything their salespeople promise me.  Does anyone know for sure if ATT never increase its rates for people enrolled in the ACP?