LR60 First Officer reported the Bombardier Flight Deck 3 App did not automatically sync updates and they were locked out of the app while dealing with a critical flight situation.

Narrative

During an incident off the coast; I attempted to access my AFM through the Bombardier Flight Deck app. I received an 'Access Denied: You have exceeded the maximum number of days this pub may be accessed without syncing. Tap the Sync button to access this Publication.' Without internet access; I was locked out of my BFD AFM. We were lucky that my PNF had a functional BFD and our aircraft carried a paper copy of the current AFM. I find it problematic that I had been using the app as the PNF 4 days prior with internet access for it to sync and the subscription didn't automatically sync. Also; the night before this eventful trip; when I was updating all of my EFB charts; company manuals; etc.; I received the warning that I had one grace day and left the app open to sync. I received no additional feedback from the app on whether it was synced; even though I thought I had. This lack of visibility of the sync status; whether a visual color indication or a countdown to sync expiration; is a human factors safety issue. All apps that use publications show you when a subscription is nearing due. Currently; my app shows a green bar with a 'Valid until date' for my 'FLT-LR60XR' which apparently has nothing to do with sync status. I still don't understand why we must sync the app so frequently. The subscription I paid for runs through a base date; so why can we not expect our subscriptions to work without syncing through our base subscription date? Suppose you require a 'license' sync. In that case; this should happen automatically without user intervention; but it also cannot interfere with the safe operation of an aircraft during a valid subscription period. When I open my company air-carrier documents app; it syncs automatically without my intervention; and if it doesn't have internet access; it warns me. When a new update is pending but isn't required; my EFB warns me but doesn't lock me out. My EFB also does not lock me out when a subscription has expired. Many operators fly with only BFD3 and no paper AFM/QRH; yet BFD3 can lock a pilot out during an incident. Paper never fails in an emergency; but the BFD3 app did. Until Bombardier updates their app; I will be very careful to manually sync the app prior to each flight.