You can't have two applications in the same immigration class simultaneously - if that's what your asking. So you have to pick one - you can't submit both.
You can only have one app going at a time. If you change your mind before they start processing, you can willingly recall your application and get a refund, then apply the other way.
Just to add - there are certainly several people here who originally applied inland, then withdrew that application, and changed to outland (i.e. resubmitted a new application via the outland route). So that certainly doable - if that's what you're asking.
Thanks for the replies.
I have applied inland for the OWP, which has been put on hold until i get AIP as i was out of status. I had wondered if i could now apply outland also. But alas i cannot - thats ok!
I can still be in the express entry pool for CEC entry though?