if you have employer-based insurance now and will continue to do so until you retire there is no need for you to take any immediate action. when you retire and lose your employer-based insurance you will have a "qualifying event" which will allow you to shop for a marketplace plan even though you are outside of the open enrollment period. you probably want to start your application and shop for plans at least two months before your employment-based plan ends.
if i plan to retire next year but not before march does the march 31 deadline for health insurance still apply? . how far ahead of losing my current insurance should i sign up? it seems best to wait as long as possible so the government can get more bugs ironed out.