My apologies in advance if this is a duplicate. I did search a bit about this before posting here.
This is related to my previous posts so, briefly: I want to leave my current position and I have another offer that I will eventually accept (not finished negotiating). I won't be able to "officially" drop the hammer for at least 1-2 weeks (negotiating, getting the offer, signing it, etc.). I teach one absolutely essential course in the fall (a core course in a graduate program) and no one else is qualified to teach it but me.
My question: In a tenure track position, what is the minimal notice period for leaving? This is not a question about "what my department would like" or how to optimize my standing with the department after leaving. This is a question about professionalism-- specifically what is the minimal notice period where the department members couldn't justifiably go around calling my conduct unprofessional. (I couldn't create a "professionalism" tag, so I tagged this with "etiquette")
Clearly, leaving one week before the semester is too late. Giving 2 years notice is probably more than enough. The answer must be somewhere in between. In my own case, I am contemplating delivering the news in around two weeks (so, over three months before classes begin).
Edit: (1) This is related to a previous question I asked
But I think it is still distinct. That question raised the issue of whether to inform my department before having a definite offer, in the interest of giving them enough time to plan. This question is about the standards of professionalism in resignation notice (analogous to the conventional two weeks in many non-academic jobs).
(2) Our contracts are year-to-year (August through April) with guaranteed renewal before tenure review. There are no specific terms written there about resignation periods. I could just fail to renew my contract (this issue would arise in about two months) but, still, the question is whether this is meets the standards of professionalism in academia, not whether it's "legal".