Hello! Yes, Transportal is still being worked on.
While I don't follow a strict release schedule, there are two major releases out at any given time. There is the public release on Itch, and there is the "early" release on Patreon (which has more content).
Loose playtime estimates as of August 22nd:
Public Release (0.4.6): About 8 hours and 11 minutes
Early (Patreon-exclusive) Release (0.5.2): About 11 hours and 11 minutes
Here is a link to the changelog for 0.5.2 on Patreon.
I'm aware that it has been a while since the last major release. I am the only developer, and I am currently in the process of a real-life move - but the game is still being worked on!
Thank you for your interest! ♥