This is unlikely since the 4.2 branch will immediately supersede the 4.1 branch, just like 4.1 did for 4.0. And the annotated listener feature won't be trivial since we intend to do a rather comprehensive revision in that space, so it does not suggest itself as a backport candidate.
Fortunately, 4.2 won't raise the system requirements: It'll be a straightforward drop-in for 4.1, just with a bunch of new and revised features.
Note that we have a rather aggressive release plan these days. 4.2 is going out by mid next year at the latest, with an RC scheduled for May. This is just about as much time as we need for proper design cycles here. Feel free to track 4.2 snapshots early as they become available in January...
There is a first cut available in 1bb2a20 (see also the event branch of my fork).
My current version needs to be largely reviewed and the project that Jean-Baptiste Nizet has provided in #16696 has interesting ideas for the post processing phase ( SmartInitializationSingleton is not invoked on lazy beans though).