Roughly, ten days ago, OnePlus excited a number of OnePlus One owners by making a specific announcement. That announcement was that their own homegrown OS, OxygenOS would be released on March 27th. As an added bonus, OnePlus also announced that the Cyanogen based alternative for the OnePlus One, CM 12S would also see its release on March 30th. Two new OSes for the OnePlus One owners out there. In fact, One Plus were so confident that they even decided to offer five OnePlus Ones as a giveaway if for whatever reason they missed either of these two dates.
Well, today OnePlus held one of their regular AMAA (ask me almost anything) type conversations on Reddit. Not too surprising, the first question put forward during the conversation was about OxygenOS and whether it will see its release tomorrow (March 27th) as scheduled. In response, the OnePlus team all but confirmed that OxygenOS will not be rolling out tomorrow "There are extremely high chances that we are giving away these 5 out tomorrow". Referring to the promise they made that they would give away five Ones if they missed the deadline.
In terms of why they are apparently being delayed, OnePlus stated that the OS is "ready to go". However, they are still waiting on certification. Another redditer did suggest that they release the OS without GApps to try and negate the certification needed and OnePlus did respond suggesting this had already been thought of "We asked. We need to pass certification even without GApps". As such, the current information on OxygenOS is that it now seems likely that it will not be landing. This, of course, could change if they do manage to get certified. In terms of when the delivery date is likely to be, Carl Pei replied to a different comment about the features of OxygenOS by saying "It's close to pure Android, but it isn't. You'll be able to see it for yourself in a few days". Further confirming, that the rollout of OxygenOS is unlikely to be tomorrow and instead is more likely to be released early next week. You can read the full AMAA by clicking the source link below.