Should we be evaluating my mother-in-law's Medicare coverage during the Open Enrollment Period?

I just saw in another post: Medicare's Annual Enrollment Period (AEP) runs from Oct. 15 to Dec. 7 this year. My MIL is in ICU, will be incapacitated for many months and only has basic Medicare. Should we be evaluating her policy and maybe make changes to her plan during this time? We have POA for her, but does that mean we can make changes to policies? She will have long term health issues from here forward, IF she comes home I will stop working to care for her.
She has NO Medigap or supplemental health insurance, I don't even know where to get line by line information to review Medicare policies....please help!