Wake Up Time, made by request of my friend unixbrain, lets you figure out what stage of the day (i.e. work cycle) your villagers are in.
Press V
(standing for Villager, configurable in key binds) for an action bar notification about what working stage your villagers are in and how long it'll take to get to working time. if it's currently working time, it'll say how much longer remains until working time is over.
If you want to configure it to be persistent, you can do so via Mod Menu.
This is named after Tom Petty's Wake Up Time, a legendary song on his Wildflowers album.