Single word antonym of "premature"

A friend of mine recently made a joke which was poorly timed; the visual irony had passed by the time she said it. I remarked that this joke was "postmature", then realized that isn't a word. Is there an antonym of premature, or can something never go past mature? For pregnancies, you can be overdue (thesaurus.com), but is there another such word that can also be extended to situations such as the one I had?

Note: I'm not looking for mature. I guess I'm asking this: can something pass maturity? Is there a word for that which can be used in a ubiquitous manner?

Solution 1:

I think stale would be the word you're looking for concerning ubiquitous manner. https://www.vocabulary.com/dictionary/stale