Unfortunately, there are problems with Oxygen Updater importing updates from the OnePlus servers. OnePlus changed their back-end, which the app used to grab the latest updates from. The new backend requires all update queries to be sent encrypted.
This means that the latest updates may not currently be available in the app. Updates are -for a limited timespan- added manually, but the timeframe of doing so is not fixed. This means it might take a few days or more from release by OnePlus until they are added.
We're afraid it's not possible to fix the importing issue, so there's no ETA for faster updates in the app. Please bear with us. For now, thanks for your support.
With kind regards,
AnonymousWP (admin Oxygen Updater) and Arjan (developer Oxygen Updater). If you have any questions, feel free to reach us at our Discord if you have any questions: https://discord.gg/5TXdhKJ.