Hi after a few hours and iterations of PD, I just nailed the re working of the Toshiba Flashair W-04 (and W-03) SD cards in a M240
after Apple's iOS 13 broke the Flashair App, which Toshiba documented here https://tinyurl.com/up62e9x
1) on the iPhone with iOS 13, remove the Flashair app completely by going into "Settings/General/iPhone Storage" and scroll down to Flashair and select "delete app"
2) power-off and then power-on the iPhone.
3) install the Flashair v4.5.0 app from the Apple Appstore
4) power-on the M240 into image Play on the rear LCD, connect iPhone to the Flashair wifi and complete app configuration.
All SD images are accessible from the M240 onto the iPhone again.
Additionally there is a new version 40004 of firmware available for the Flashair W-04 available here https://tinyurl.com/sfgtw8m