Apple has just released iOS 14.2.1 to the public. You can download the update on your iPhone now by heading to Settings > General > Software Update.
Here are the release notes from Apple:
iOS 14.2.1 addresses the following issues for your iPhone:
– Some MMS messages may not be received
– Made for iPhone hearing devices could have sound quality issues when listening to audio from iPhone
– Lock Screen could become unresponsive on iPhone 12 mini