Hi Kosta and Ashley,
I've just discovered a bug. I've gone back to previous builds and it looks to have been introduced in build 85, and remains in build 86. It is not in build 83.
At the start of a sentence for example, the first letter is set to be upper case automatically. However you can change this to lower case by using either the 3D touch or the two finger tap gesture.
When I do this, I hit a bug after completing that first word and moving on to the next word or punctuation mark. On that word or punctuation mark, I can only swipe gown once, for example to the comma. After that it freezes up. A swipe left will then delete all of the text I had typed up to that point.
I hope that description is making sense. I will record a screen capture if needed.
I am on an iPhone X running iOS 12 beta 1.