Good news, Flashforge today (27th August) confirm the connection as per the attached image will work.
https://photos.smugmug.com/3D-Printe...ch-FFCP-XL.jpg

Originalt80 you can test by sending the following g-code:
M280 P0 S10 ; sensor pin down
M280 P0 S90 ; sensor pin up

Thank you.