All three devs can be found on Twitter, and as of January 2019 they're all alive (no info about the artists' health given). Just skimming through their accounts I can't see any of the three mentioning Spirite Parade anywhere except in their bios.
Akane (@akanekari) has been the least active, but her last activity was on January 21st where she replied to Rins.
Rins (@lettucetown) has been more active than Akane on Twitter, but even then there was a gap between June 2018 and December 2018. Her last Twitter activity was on January 16th 2019.
Lore (@yandere) has been most active on Twitter. A quick scrolling through her timeline shows that she's been frequently tweeting and retweeting about all kind of stuff, ranging from other people's projects to real life stuff.
I can understand that real life can take someone's attention away from the internet and social media, but seeing how the writer has not only been online but also has the time to promote other projects and whatnot, I find it very disappointing and upsetting that she apparently can't be bothered to update people here who have spent real money on their game. They promised monthly updates, but even that promise only lasted three months aka three meager posts before they disappeared again.