I agree that development has been rather slow lately. Since the start of the year it has been around 2 months for each update. Version 0.18 had one new scene really. Version 0.19 is set to release at some point in August (that's over 2 months since 0.18) and will include one new scene with Linda (however, it's going to be a scene similar to the holiday special, so there's arguably a lot more programming and artwork necessary for that scene).
@Monke4Life: I don't quite follow how you come up with 16 years. Siren has stated on their Patreon page that there are going to be about 4 more updates to this game before it's finished. I suspect that will include getting Emily into the group activities and maybe a final scene with all 3 of them. Siren has stated they're most likely planning to continue the story in another game.