Not sure on the answer but we will find out.
It looks like they are going to require P Mode to use the SDK instead of F, but only on the P4 (confusing). Here is the documentation:
typedef NS_ENUM (uint8_t, DJIRCHardwareFlightModeSwitchState){
/**
* The Remote Controller's flight mode switch is set to the F (Function) mode. For the Phantom 3, Inspire 1 and M100 the remote controller must be in Function mode to enable Mission Manager functions from the Mobile Device. It is not supported by Phantom 4 (which must use P mode for the Mission Manager functions).
* The Phantom 4 remote controller flight mode switch is labelled A, S, P from left to right.
* The Phantom 3, Inspire 1 and M100 remote controller flight mode switch is labelled F, A, P from left to right.
* Independent of label, any remote controller (P3, P4, Inspire 1, M100) used with the Phantom 3, Inspire 1 or M100 will report F mode as selected if the switch is set to the left position.
*/
DJIRCHardwareFlightModeSwitchStateF,
/**
* The Remote Controller's flight mode switch is set to the A (Attitude) mode. Attitude mode does not use GPS and the vision system for hovering or flying, but uses the barometer to maintain alititude. If the GPS signal is strong enough, the aircraft can still return to home in this mode.
* The Phantom 4 remote controller flight mode switch is labelled A, S, P from left to right.
* The Phantom 3, Inspire 1 and M100 remote controller flight mode switch is labelled F, A, P from left to right.
* Independent of label, any remote controller (P3, P4, Inspire 1, M100) used with the Phantom 4 will report A mode as selected if the switch is set to the left position.
* Independent of label, any remote controller (P3, P4, Inspire 1, M100) used with the Phantom 3, Inspire 1 or M100 will report A mode as selected if the switch is set to the middle position.
*/
DJIRCHardwareFlightModeSwitchStateA,
/**
* The Remote Controller's flight mode switch is set to the P (Positioning) mode. Positioning mode can use both GPS and the vision system (when available) to fly and hover. For the Phantom 4, P mode must be used to enable Mission Manager functions from the Mobile Device.
* The Phantom 4 remote controller flight mode switch is labelled A, S, P from left to right.
* The Phantom 3, Inspire 1 and M100 remote controller flight mode switch is labelled F, A, P from left to right.
* Any remote controller (P3, P4, Inspire 1, M100) used with any aircraft will report P mode as selected if the switch is set to the right position.
*/
DJIRCHardwareFlightModeSwitchStateP,
/**
* The Remote Controller's flight mode switch is set to the S (Sport) mode. Sport mode can use both GPS and the vision system (when available) to hover. Sport mode is only supported when using the Phantom 4.
The Phantom 4 remote controller flight mode switch is labelled A, S, P from left to right.
The Phantom 3, Inspire 1 and M100 remote controller flight mode switch is labelled F, A, P from left to right.
Independent of label, any remote controller (P3, P4, Inspire 1, M100) used with the Phantom 4 will report S mode as selected if the switch is set to the middle position.
*/
DJIRCHardwareFlightModeSwitchStateS
};