does anyone know if seniors are eligible for ACA.

[enough]

13. On Medicare myself, having heard various things, I went to the Medicare website,

and it plainly states that Medicare is not part of the ACA.

We do still have the usual annual enrollment period (which ends on December 7 this year) if we want to make any changes to our Medicare enrollment.

http://www.medicare.gov/about-us/affordable-care-act/affordable-care-act.html

Quote from the site>

1. Your Medicare coverage is protected.

Medicare isn’t part of the Health Insurance Marketplace established by ACA, so you don't have to replace your Medicare coverage with Marketplace coverage. No matter how you get Medicare, whether through Original Medicare or a Medicare Advantage Plan, you’ll still have the same benefits and security you have now.

You don’t need to do anything with the Marketplace during Open Enrollment.

more at the site>