Notwithstanding the provisions of this title and chapters 164, 170 and 204 and any special act, municipal charter or home rule ordinance, a municipality, upon a two-thirds vote of its legislative body, may amend its charter for the sole purpose of modifying its budget adoption dates. Such budget adoption dates may include, but need not be limited to, applicable dates relating to an executive presentation of a proposed budget, public hearings, fiscal authority action, publications, referenda or final budget adoption. Any vote by the legislative body of a municipality pursuant to this section shall include a reference to this section. For the purposes of this section, “municipality” has the same meaning as provided in section 7-401.