I have a Sony Xperia SP that is currently network locked to O2-UK, I am having it unlocked to any network in the next few days.

My problem is I know Android 4.3 (my phone runs 4.1.2 at the moment) is out for the SP on unbranded handsets right now, and most networks have started pushing it out to locked phones, so my question is.. once my phone is unlocked will I be able to download 4.3 straight away or will I have to wait for O2 to push it out still?

Thanks in advance!