Canon EOS RP, Advanced User'S Manual, Page: 534 / 612

534
Custom Function Settings
C.Fn II-6: Orientation linked AF point
You can assign AF points or Zone AF frames to different positions based on
whether you are shooting vertically or horizontally.
z
0: Same for both vertic./horiz.
AF points or Zone AF frames in the same position are used for both
vertical and horizontal shooting.
z
1: Separate AF pts: pt only
Separate AF point or Zone AF frame positions can be assigned for
each camera orientation (1. Horizontal, 2. Vertical with the camera grip
above, 3. Vertical with the camera grip below). Useful when switching to
AF points or Zone AF frames in other positions automatically based on
camera orientation.
AF points or Zone AF frames assigned to each of the three camera
orientations are retained.