A fellow user, here:
Time blocking is the whole reason I downloaded GoodTask! I kept seeing comments from ADHDers saying they needed to replace the now-defunct perfect app “30/30,” and GoodTask was a common answer.
I figured out a way to sort-of time block in GoodTask, and described it in Relative time 200+? . Of course it would be nice if time blocking became a more clearly-defined feature.
Hope that helps!