At the moment its anywhere from 2-3 months.
I work a full-time job that doesn't pay great and renders take around 20mins-2hours depending on the scene so if you base an update around 800 renders you can do the math and work out how long the process is. < this is without gui, post-processing, script writing, coding and learning.
One thing I take pride in is my renders and quality, I could even push it further if I wanted to. But I have to find a happy medium where I can produce decent enough quality in a timeframe that's somewhat suitable, even though I'd love to deliver updates sooner, I can't at the moment.
If or when patreon/substar kicks off more, I'll be able to dedicate more time to the game.
Thanks,
Dob