Replace cell reference

[Rock5150]

Hello

I have the following formula in a cell. If I wanted to change say DM89 to DM56 for example as there would be 56 rows, how do I do a simple replace or is it even possible. That way I don't go in the formula and move the cursor over and manually delete 89 and put 56. Or even one step further, if there were only 56 rows of data, is there a way to tweak the below formula to only select the range up to the last known cell with data assuming no spaces after the last enter and a straggler say 4 or 5 cells below?

=IF(ROWS($DE$2:$DE2)>COMBIN(COUNTA($DM$2:$DM$89),2),"",INDEX(DM$2:DM$89,LOOKUP(ROWS(DM$2:DM2)-1,COMBIN(COUNTA($DM$2:$DM$89),2)-COMBIN(COUNTA($DM$2:$DM$89)+1-ROW(INDIRECT("1:"&COUNTA($DM$2:$DM$89)-1)),2),ROW(INDIRECT("1:"&COUNTA($DM$2:$DM$89))))))

 

[LazyBug]

Hello, @Rock5150!
Answer to the first question only:
1. select the cell with the formula,
2. press Ctrl+H (call the Find and Replace dialog box),
3. in the "Find what:" field enter $DM$89 and in the "Replace with:" enter $DM$56,
4. press Enter.