I saw many times notice longer than 6 months; the record so far is more than 2 years, but these are special cases: - very high level people like VP level or abo

I saw many times notice longer than 6 months; the record so far is more than 2 years, but these are special cases: - very high level people like VP level or above - 6 months during which they fully onboard a replacement - a former colleague that was past retirement age, but they had no replacement for him so they convinced him to stay longer (he gave 2 years notice) - my boss is on notice for retirement in more than 18 months from now (he can retire any day he wants, he was the age and he is meeting all criteria) But other than that, I don't recommend a notice longer than 1 month, that is enough for almost any case.