I wonder what is the historical frequency of these kinds of "fake spring" phenomena. How many times a decade these happen per location? Whatever that number is, I bet it is increasing and will keep increasing until it is a common thing. This is of course more marked on the lower northern latitudes and moving Northward. As the winter "heat spells" become longer, more intense and more frequent areas that for millennia were ideal for these perfectly adapted trees will no longer be so.
Of course this will be somewhat mitigated by ideal areas for cultivation being created much further north. Russia and Canada might like that, for however long it may last.