From Politico:

March 25: Final enrollment deadline extended. The March 31 deadline — the end of enrollment for 2014 — will be loosened for people with special sign-up circumstances.

March 14: High-risk pools extended. The special, temporary coverage for people with serious pre-existing conditions — which was supposed to last only until the health insurance exchanges were in place — was extended a third time for another month.

Feb. 10: Employer mandate delayed. This time, businesses with between 50 and 100 workers were given until 2016 to offer coverage, and the mandate will be phased in for employers with more than 100 workers.

Jan. 14: High-risk pools extended. The high-risk insurance pools, which originally had been slated to close Jan. 1, had already been extended once.

Dec. 24: Enrollment deadline extended. In a message on HealthCare.gov, customers were told they could get help finishing their Jan. 1 applications if they were already in line on Dec. 24.

Dec. 12: Enrollment deadline extended. Customers on the federal enrollment website were given nearly two more weeks to sign up for coverage effective Jan. 1.

Nov. 27: Small Business Health Options Program (known as SHOP) delayed. Online enrollment for the federal health insurance exchanges for small businesses was delayed.

Nov. 21: Open enrollment delayed for 2015. The administration pushed back next year’s enrollment season by a month.

July 2: Employer mandate delayed. The administration declared that it wouldn’t enforce the fines in 2014 for businesses with more than 50 full-time workers who don’t offer health coverage. The fines were pushed back to 2015.

Nov. 15, 2012: Exchange deadline delayed. The Department of Health and Human Services gave states an extra month to decide whether they would set up their own health insurance exchanges — a decision it announced just one day before the original deadline.

There are many more, but this is just a start.