First of all, see this thread from 2017.

I had concluded, long before now, that this series is done and over with forever - yet newly have learned it'll be resuming, with a brand new season, on September 20th!

Following, from TV GUIDE magazine's Sept. 14-27 double issue, is an article authored by Kate Hahn:

We're so bloody happy! Returning after a three-year absence is Sally Wainwright's brilliantly written British comedy-drama about an extended Yorkshire family trying to do the best they can as life's baggage accumulates. At the show's unsentimental center: conservative Celia and liberal Alan (Sanditon's Anne Reid and Derek Jacobi), octogenarians who joyfully got engaged in the series' 2013 U.S. premiere [aired Nov. 2012 in the UK] after the passing of their lifelong spouses. // Now in Season 4 (No. 5 in the U.K.), seven years into wedded bliss, they're at odds when he goes back to work....Their middle-aged daughters - posh head of school Caroline (Sarah Lancashire) and sheep farmer Gillian (Nicola Walker), both moms - clashed initially but bonded when Gillian confessed she'd murdered her abusive first husband. The two find trouble on the job, and, Walker notes ominously, "We have shared enemies."

I don't actually remember, anymore, where things last left off, but look forward to finding out how things will continue!

Back when Seasons 1-3 aired, I hadn't believed this would be the type of series that would at all interest me, therefore opted to completely bypass it. Then, I think during Summer 2016, on weekday afternoons, one of my PBS stations ran all three seasons (I believe one episode per day on multiple days of each week), I chanced upon an early (possibly the very first) episode and quickly realized this is good stuff and that I was intrigued, interested, and hooked, so thereafter watched and enjoyed all the remainder that aired. (I don't remember if I ever saw the two Christmas 2016 subsequent episodes [which are considered Season 4 in the UK, but that are considered a freestanding 2-part holiday special in the States].)

Here's the Wikipedia article about this series.

Incidentally, Season 4 (which aired half a year ago in the UK) will have four episodes.

Please check out the following list of titles and celebrities I've created TMDb threads for: https://www.themoviedb.org/list/118052