An incorrect date is any date which is not of the form абҵарамза 2023, e.g. абҵарамза 28, 2023, or june instead of June, or other spelling mistakes.
DMCA stands for "dated maintenance category – articles". Similar templates exist for certain other namespaces or combinations. DMCA is a metatemplate with highly circumscribed use, and not intended to be "editor facing".