CountIF blank cell adjacent and also before a nominated date

[ValyrianSteel]

Hi,

I am looking for the formula to be able to essentially create a resource profile using the dates when work is scheduled to complete.

Attached image showing Column R is always populated with a forecast completion date and S is when the work actually completes. I am looking to populate the table in the other image where it calculates a sum of all the work which will be going on each month and have been trying to just do the calculation if the cell in Column S is blank. I have been getting results but they don't seem to take into account the date in column A in the 2nd image.

Any ideas be really helpful!

 

[ValyrianSteel]

I realise that I also need to calculate if the cell in the same range is not past the date in A2

 

[ValyrianSteel]

Utilised a start and end date

=COUNTIFS('The Plan'!$AK$1:$AK$188,">"&$A14,'The Plan'!$AK$1:$AK$188,"<="&$A$61)