Plan upgrade

My Magenta plan was forced to change to Experience Signature this month, which I really don't want or need and I'm so pissed off that price went up $25 total. I have total 8 lines (4 are free lines for life). This Experience Signature has no benefits for trade-in/upgrade, no promotion at all. Now I see they have the Experience More with Appreciation Savings, and price will drop $25 total. Is this price locked? Or just for 1-2 years? And do I have trade-in promo like regular Experience More/Beyond?