Ok, this isn't simple, so you need to make a decision.
There are, effectively, four states:
Not started
Started, not finished, gaps
Started, finished, gaps
Started, finished, no gaps
I can give you three separate formulae which will indicate the states, however, combining them would make for a very complex and unmanageable formula. And, if it were repeated many times, it might have an adverse effect on performance.
My recommendation would be to have three separate columns and filter on them as required:
The last formula actually highlights gaps at the end so, in itself, it isn't necessarily a true reputation, as a gap of one or more cells at the end would imply "not finished". So, you can see where I'm going with this.
Happy to provide code to put those three formulae into code if you're happy with that as a compromise.
Regards, TMS
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