well the game's almost 80% programmed all that would be left are just assets art and sound. i already have a ton of unused models i cant wait to make use of and as far as art goes i'd only really use it on the UI, which im designing to be simplistic as forget
ive been doing unit and integration testing up the ass so i know everything has been bug tested thoroughly already. the only source of bugs i can imagine would be the not-yet-made save system
the 4 month deadline is just for the game to pass the system tests, there'd probably be another month dedicated for acceptance testing, as well as a month or two after for beta tests. all of these deadlines are subject to change but im definitely going to try and keep all development under 8 months
any developer worth their salt will confirm that unit testing only catches the least offender bugs - the worst offender bugs are those you cant catch just by testing that the function works as intended.
that said, considering it seems to be a small game, you may be able to get away with it. its just a warning i suppose. dont be surprised if it takes a lot longer to finish all the art and sound assets or if people dont like you left out feature x or tutorial y cause you skipped making it out of reducing complexity