I think the form he's talking about is the "Schedule A Background/Declaration: form. The reason this form might have to be filled out by hand is that there is one section to "write" your name in your native language. Idk if it applies to native English speakers or languages with English characters, but everyone else has to write it in the native letters or script. The word "written" is why I think we need to print it out and sign by hand.
Form "Additional Family Information" needs to be signed too.
Another Tweet, later yesterday