What to do when the correct answer to a question changes over time?
Say a question is asked/answered as per usual and after some long period (say 2-3 years) a change in technology or otherwise causes an answer that has less votes than the originally accepted answer to be more relevant (or correct) currently.
What is the expected procedure here? Should the original answer be down-voted? Should the question and its originally accepted answer be tagged somehow as irrelevant/redundant? Should the original question/answer be left and a new question (exactly the same) be asked to allow the answer/vote process to begin again?