Can't update to 3.5 via Mac App Store

TaskPaper 3.5 seems to be a whole new app in Mac App Store with no ability to upgrade from previous version. Also I can’t run previous one on Sierra. Do I need to buy it again?

Yes TaskPaper 3 is a paid upgrade. There’s a 50% off upgrade discount if you owned a TaskPaper 1 or 2 license.

More information upgrade discount is here:

More information on why TaskPaper 2 stopped working on Sierra is here: