Heller was not a change of mind by the supreme court (it ruled on a different matter to previous rulings -- which had explicitly skirted around the problem of civilian ownership of weapons outside of a military context).

However, even if it were a change of mind -- the supreme court changing its rulings is an incredibly rare event because such events question the finality and authority of their decisions.

Hence why I said "the only way to change their decision would be through a constitutional amendment" -- because waiting for the supreme court to change their mind about it (while technically possible and sometimes the case) is hardly a useful policy position for a political argument.