Just spoke to Apple Care. There will likely be a device update to permanently fix the issue, but they gave me a temp solve that worked:
- go to settings, general, keyboard, text replacement
- hit the plus sign to create a new text replacement
- in the “phrase” bucket type a lower case “i” and in the shortcut bucket type an upper case “I”; then hit save
- hit the plus sign to create a second new text replacement
- in the “phrase” bucket type an upper case “I” and in the shortcut bucket type another upper case “I”; then hit save