Sudden Change in PTO - Company Refusing Time Off/Pay Out

Hello! Love this group so much, and hoping someone might be able to help and provide some advice. On 11/11/2020, my company announced that beginning 01/01/2021, salaried employees will have unlimited PTO + 10 sick days 6 floating holidays. HOW AWESOME! However, I quickly learned there was a large caveat. Since beginning this job, our benefits included 80 hours of roll over time. I 100% anticipated using anything over those 80 hours (of which I would be at 71 hours on 12/31/2020) before 12/31/2020. However, as a MN employee, my company has indicated we will get no time rolled over into 2021. ZERO. Frankly - I am astonished they are giving us 6 weeks notice of this change of plan. I have seen companies do this in the past, but they provided 12 month notice! I am in a really tough spot - as this means I will need to take 18+ days (not including Thanksgiving and Christmas Day) off before 12/31/2020 - putting my colleagues in a really tough spot. I feel terrible! However, I also feel that I earned my PTO - including covering for two colleagues maternity leaves, working on average well over 40+ hours per week, etc. Taking emotion out - when I became employed, it was my understanding that we "shook hands." I work, my company pays me for that work, per our contract. All in all, I am looking for some advice. Is my company legally obligated to either: Approve my time off OR If they do not approve, write me a check for the time I will not get to take off? Help!! :) Thank you so much in advance for any and all help/advice.