What should be done, from an application perspective, prior to performing an SRDF Failback operation?

A.
Stop accessing the R2 devicesStart accessing the R1 devices after the command completes

B.
Stop accessing the R2 devicesStart accessing the R1 devices before the command completes

C.
Continue accessing the R2 devicesStart accessing the R1 devices after the command completes

D.
Continue accessing the R2 devicesStart accessing the R1 devices before the command completes