https://wccftech.com/heres-when-ios-13-4-will-be-released-in-your-local-time-zone/

It is widely expected that Apple will release iOS 13.4 to all users on March 17. If you have been looking forward to the forthcoming update but don't know what time it will be released then you have come to the right place. Check out the devised list of regions with associated time zones if you're interested in checking out the release time.

iOS 13.4 rested in the beta phase for quite a while. The company has released five beta builds so far and it is all set to release it to the public. Take note that the company has not officially announced iOS 13.4's release date but it is expected to arrive today.