No, the dev is active on both patreon and discord. Probably he is trying to work around patreon's new rules which will be a tough one for dual family. But the good news is we might have an update coming up very soon.
Dual Family is so deep into it's development, and it's whole premise is around the Family, just look at the title... He/she is almost better off moving to another crowd sourcing method or site, if they want to keep Dual Family going without butchering it to death to convert... That or take the easy route, and just end the game, and move on to a new project if they are so dead set on keeping with Patreon...
For me, when I see one website dictating to a developer the direction of a project just to keep the money flowing, shows a form of greed over creativity... There are lots more options for crowd sourcing, including just taking direct donations rather then a subscription method... If the desire to stick to Patreon is that strong, it almost makes you wonder if the project was never about making something they wanted to make, but to make something that just guarantees a huge income via subscribers over just normal donations... I think they are better off scrapping the project and making something new anyways... Dual Family has so many issues, in my opinion... And doing a major overhaul this deep into it, is going to have loss in revenues regardless, especially if it all ends up sounding weird post-conversion... I've seen some other major conversions that just ended up sounding bizarre, or having lots of mistakes in the conversion... Remember, even adopted and/or step children in a family sex scenario is considered incest in some places, and what is the likelihood that Patreon will still give the boot for it?