Time format does not work for AM

After I changed the time format to 12 hours AM/PM from the files scheduler.js and

scheduler.config.xml_date="%Y-%m-%d %h:%i %A"; , I cannot schedule any time in the morning (AM). They all moved to PM section which is weird. Can anyone tell me what i did wrong?

Be sure that data contains time in valid format ( have AM|PM )
If issue still occurs - please provide a sample of data for which such problem occurs.