I just called the CIC today. For the information of everybody let me correct some of the false information being shared here when your OWP app is returned.
If you sent your OWP+PR and say for example the owp was returned to you, then you sent them back immediately it is NOT TRUE that you need to count another 4 months from the day you resubmitted it.
They will consider the date when you originally sent both apps.
If you DID NOT APPLY FOR PR and just OWP app, for some reasons they returned it to you, IT IS TRUE you will be waiting another 4 months again from the date you resubmitted, it is mainly because your application didnt come with any PR app.
Hope this helps!