Date Formula Spans Extra Day

[ClaireMcF]

Hi

I'm using this formula to conditional format a group of cells, in a Gantt Chart style format.

=IF(AND($E3<=M$2,$F3>=L$2),1,"")

But why is the extra day always tagged onto the end date in the gantt chart bar

End date i 15-Feb, but the bar extends to 16-Feb

[#2]

@ClaireMcF 

To which range has this rule been applied?

[#3]

It applies to the whole of the Gantt chart, so the conditional format was keyed against cell AR3 and applies all the way through to QQ103

[#4]

@ClaireMcF 

But the rule refers to L2 and M2 - shouldn't L3 or M3 ave been the active cell in the selection?

Could you attach a small sample workbook demonstrating the problem (without sensitive data), or if that is not possible, make it available through OneDrive, Google Drive, Dropbox or similar?