Hi, A small follow-up: I added a characterization test for the current behavior; commit 8a13d1fef.
The test uses a regular level-30 headline and confirms that column summary computation currently signals `args-out-of-range'. Therefore, the practical effect is not merely that deeper headings fall outside the accumulator; they can cause `org-columns' to fail. This also makes the situation closely analogous to `org-clock-sum', where commit 9059c8fae removed the fixed hierarchy-depth limit by growing the per-level accumulator as needed. After removing `deepest-level', the test can be changed to expect the level-30 value to be summarized normally instead of expecting an error. Best, -- Slawomir Grochowski
