Prior to the third maintenance release of SAS^® 9.4 (TS1M3), the DATESTYLE system option determined the order of the date components only when AM/PM was not included at the end of the date value. For example, when the ANYDTDTM informat is called to read a value like the following, the MDYAMPM informat is called behind the scenes to read the value:

If the AM/PM portion is not included with the value, the DATESTYLE system option determines the order of the date components, if the components are ambiguous.

Beginning with the third maintenance release of SAS 9.4 (TS1M3), the DATESTYLE system option determines the order of the date components regardless of the presence of AM/PM in the value.