Now RadioTimes.com can reveal that there is talk of a ten-part run for the next series, which is also a massive hit on Amazon in the US.
All three series so far have run for six week so far, but the plan is to extend that according to sources.
It is understood that the writers are seriously considering the move, which is backed by Channel 4 and Amazon.
But after that? Well, we may have a fairly long wait before the fifth series returns to the trouble-laden couple Rob and Sharon.
Delaney assures RadioTimes.com that he and Horgan are taking a break before writing series four, and a fifth could have an even longer gap if it is commissioned.
“We sort of think of our spiritual forbear as the Before Sunrise, Before Sunset films,” Delaney tells us. “They rather beautifully dip in once every ten years on this couple and that’s a rather amazing way to tell a story.”
One reason for this is the stunning success of Catastrophe, which has made the pair in demand stars in the UK and US.
Horgan is overseeing a second series of US comedy Divorce starring Sarah Jessica Parker and is co-writing a full series of her BBC comedy Motherland.
Delaney, who has a young family, is expected to announce a stand-up tour very shortly.
Ben has worked as a professional journalist specialising in TV and the arts for nearly twenty years. After a two year stint on local newspapers in the mid 1990s, he spent more than 5 years as the broadcast reporter at the Stage newspaper. Following that he enjoyed staff reporting positions at the Sunday Mirror and the Sunday Times breaking stories and writing features before settling as a full time freelance writing for an array of newspapers and magazines - but mainly for the Guardian, Evening Standard, Broadcast, Independent and the New Statesman where he wrote a column.