Have some large not fixed length of data in Excel in multiple columns. I want to list 2 columns (timestamps) in another worksheet with =UNIQUE(Sheet1!M:N;FALSE;FALSE), but filters out empty cells. Empty cells can cause UNIQUE function to add an additional row, and if formatted it to date it will contains 1900/01/01.

If I set the ranges to M1:N345 it is good, but the data is variable length in every sheet.

ChatGPT really unusable for this task...

How can I skip the empty rows, or iterate only where it is data at this columns?

Thanks!

EDIT: Added sample excel code