https://wccftech.com/jailbreak-ios-13-4-with-new-checkra1n-0-9-9-experimental-release/

Apple seeded iOS 13.4 and iPadOS 13.4 GM to developers a few days ago. As per the latest, Checkra1n has released an experimental release that offers early jailbreak support for devices running iOS 13.4 and iPadOS 13.4. Apple's latest firmware has a lot to offer considering the number of forward-facing features it has to offer. If you were looking to update to the latest build but didn't want to lose your jailbreak status, then now you can. That's right, Checkra1n has released its 0.9.9 experimental release, which you can try right now on supported iPhone and iPad models.

Take note that Apple has not officially rolled out the latest iOS 13.4 and iPadOS 13.4 to the public. However, the company is set to release it in the coming week. If you're running a Golden Master build of iOS 13.4, you can use the link embedded in Luca Todesco's tweet to jailbreak your iPhone and iPad. That's right, Checkra1n 0.9.9 experimental release is not available on the jailbreak website. If you want to try it out, you can access it through the link that was published with Luca Todesco's tweets.