If your application is delayed, it’s usually for 1 of 2 reasons: you may not have enough public watch hours (Creator Studio shows public & private combined), or our team couldn’t come to a clear decision & we need multiple reviews. More info: https://yt.be/help/YPP-review
Sorry to hear that you've been waiting so long, our team doesn't have specific timelines for individual channels but hopefully you don't have to wait much longer for your update. Thanks for your continued patience.