I know all you iPhone users with the latest update are having a problem with the i glitch. Well, Here is how to fix it:
Go to settings, general, keyboard, text replacement, and tap the plus sign.
In "phrase," type an uppercase "I." In "short-cut" type a lowercase "i." This overrides the autocorrect so that every time you type a lowercase "i" it will change to an uppercase "I."
Apple will eventually fix it with the next software update. Good luck!