Does Anything Reset Casual MMR?

Question

Is Casual MMR reset for any reason in Hearthstone?

For example, do any of these have an effect on my MMR?

• Character changes
• End of month
• A long break from play

Answer 1

During the beta of Hearthstone Aratil a "blue" (customer service rep) on the Battle.net forums indicated that while ranked play MMR reset with each season casual MMR did not.

Unfortunately, Blizzard has closed the beta forums, but the Blue Tracker at Hearthpwn captured the question and answer. To my knowledge there have been no further updates on how MMR works from Blizzard.

Answer 2

Casual MMR does not reset.

SOURCE