[plugin: gigpress] incomplete date entry

i am currently running gigpress 2.2.4 on a test site. the archive feature is great for past dates and i am wondering if there is a hack to allow incomplete dates? i have plenty of show listings where there are incomplete full dates due to unknown days or months (e.g. 1993-04-xx 1992-xx-xx) and i would rather have something incomplete as mentioned above even if it must be 2013-01-00.

by any chance is this possible to implement using some kind of hack? if so, what must i add and where within files?

thank you very much.