At a Sherlock event on Tuesday night, organized by the Royal Television Society in London, series creators Steven Moffat and Mark Gatiss teased what’s to come in series 4 of the detective drama.

Perhaps most surprising out of the event is this from The Hollywood Reporter: Sherlock series 4 is “expected” to debut in 2016, which obviously is a long wait and conflicts another report in January that said the show could be ready by this Christmas 2014.

BBC controller of drama commissioning Ben Stephenson was also on hand at Tuesday’s event with Sherlock’s creators, which may lend credence to 2016 being an accurate timeframe. While no one is quoted in THR’s report, the creators do talk about the difficulty with scheduling because of the popularity of the show’s stars, Benedict Cumberbatch (Sherlock) and Martin Freeman (Watson).

Related: Six stories we’d like to see in Sherlock series 4

Elsewhere during the event, Moffat and Gatiss hinted at what’s to come for the two detectives in the new episodes. For starters, Moriarty will “be featured in the new season,” and Moffat reiterated that their plan to bring him back (after teasing his return during the series 3 finale) had been set in stone for a while.

THR says the creators also teased bigger roles for the women of Sherlock. They reportedly suggested “the show is likely to see increased roles for female characters Molly Hooper (Louise Brealey) and Mrs. Hudson (Una Stubbs).” In addition, new female characters “could” be added. Moffat and Gatiss did not offer specific details, as the show is historically very secretive about future plot lines.

The gap between Sherlock series 2 and series 3 was two years long, so while fans are accustomed to a long wait, they’ve been hoping that gaps between future seasons would be sped up as the show continues to gain popularity.

As always, we’ll keep an eye on any and all reports about the Sherlock series 4 air date and pass them along to you.

Thanks, THR.