That's about 15 days before your certificate would expire if you got one today.
That's a little strange as usually it is scheduled about 30 days before expiry. You might have changed RenewalDays in a configuration file or you might be using an old version of letsencrypt-win-simple (recently renamed to win-acme) that does things differently.
Letsencrypt-win-simple/win-acme usually creates a Windows scheduled task to automatically renew your certiticate for you. You can check the Task Scheduler in the Control Panel to confirm one exists.
It runs daily and checks the registry to see if it has to renew a certificate. It only renews the certificate when the registry says it’s time to. You can run letsencrypt-win-simple --renew on the command line yourself to see it in action.
When you got your last certificate, it should have scheduled a date two months afterward to renew it, just as it did this time.
If you forgot about that and just renewed it a little bit early that's no problem. Better safe than sorry!
If your certificate was getting really close to expiring or expired on you and it seems like the automatic renewal thing didn't work like it should this time then we should look into that.
You can only turn it OFF with --notaskscheduler. It's on by default, and you showed me it was there in your task scheduler screenshot.
Everything else like the time the daily task runs and the days to wait to actually run the renewal are set in its configuration file, but @WouterTinuspointed out in another thread recently that changing these settings will only take effect the next time it is actually renewed.