Ultimate Classic 300 being "upgraded" to Ultimate with "outdated modem"

I got one of these notices on March 8 and it states I have until March 29th to upgrade my equipment or I will be moved to a plan which has 500 down / 10 up. The ultimate classic I have now has 300 down / 30 up. This is a serious bunch of BS and illegal. Cox surely has the right to require an equipment change. However, the law says they must give 90 days notice. Changing me to a plan that is not equal or greater than what I have now is also not legal. I have a contract. That is what I signed for. The law says I have the right to own my own equipment. I just spent an hour on chat with Cox. They want me to upgrade to the Giga plan for the same amount I'm paying for 12 months that after it goes to $120 a month. BUT if I want the Giga speed I need to upgrade the modem of course. So i will still have to pay $150 for a new modem or lease it for $12 a month.

But here is the real crazy sh*t.... I was under the impression that my modem would not be compatible with the network after March 28th. However, the Cox rep tells me that if I upgrade to Giga service now, I can continue to use my Docsis 2 modem on the network but I just won't get the 1 gbps down. This is nuts. So basically, it's not a modem compatibility issue. Cox just wants to cut everyone with 30 mpbs upstream at $99 per month. With all the people working from home, the 30 mpbs is crushing the network. So they came up with this BS that you must downgrade your upstream or you must upgrade to a new modem if you want to continue your current plan. They know *** well that people who are out of work right now can't afford to buy a $150 to $250 new modem so they need to take the downgrade or get locked into a new plan with higher monthly rate or pay $5-$12 additional a month to lease a modem from them. They have been trying to get me to upgrade my service package for a year now and I refused. They cant even get me the 300 down / 30 up I'm paying for now so why should I suspect if i upgraded to a faster service I would get what i'm paying for right??      

Again, forcing an equipment is acceptable and legal. However, 20 days notice is not. The law says the provider must give 90 days notice before forcing an equipment upgrade that will change my current service. Thus, Cox needs to either provide me with a free modem to use for 90 days from the time the service change takes effect, at no charge, or they must continue to provide me with the current 300 down / 30 up I'm receiving now with the same modem for 90 days from the date the noticed me which is March 8th.   

LOL - I'm still on chat with Cox now as I type this. It is now over 1 1/2 hours with no solution. My options are:

1) Either I agree to take the Giga service upgrade for what I'm paying now then $20 more per month after 12 months AND I can keep my current modem if i don't care about the giga speed down

2) or I lease a docsis 3.1 modem from them for $5 per month, or

3) I take the downgrade to 500 down / 10 up and keep my current modem.  It really makes no sense why I can't keep my modem and keep my current plan speeds. Especially, if they can do it, IF I sign a new contract to pay an additional $20 per month after 12 months. This is extortion. Cox knows you have a contract but they don't care. You either pay them more by leasing their equipment or you pay them more to keep the service you have. It can't be any clearer. Luckily I have this whole chat saved. I'm sure there are going to be a lot more people pissed off and this is not going to be the end of this for Cox. I foresee some big fines coming ahead....