Hi Iss,
Yes, with strategy 20, sales orders consume PIRs in SCM APO, if you have made all settings correctly.
Normally you cannot set the categories of the PIRs. All categories that marked as 'Forecast' in "Category type" field in /sapapo/atpc03 will be consumed by sales orders. Please check my KBA 1886859.
For further information about forecast consumption, please check wiki page http://wiki.scn.sap.com/wiki/x/-RbMFw
Best Regards,
Ada