Soon: When will Node-RED 4.0 be released? - #6 by knolleary
If you want to take money to the bookies, "this month" is even odds.
There has been discussion about this. Certainly, v16 will be skipped. Not 100% sure if 18 or 20 will be the new minimum.
Of course, there is nothing stopping you or anyone using Node v18 or 20 with 3.1.6 today 
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