Hello rejishkr, You can replace the disk in slot 11 as since it is bypassed it has been taken offline.  When you replace the drive if you are still getting the bypassed error then we will need to get a support bundle from your MD so that we can look at the errors & see what is causing the drive to be bypassed. Please let us know if you have any other questions.
We are using MD3220 as DAS, configured and  managed using Powervault MDSM.  Physical disks at slot 8,9,10 and 11forms disk group 3 in RAID 10 configuration. Recently at slot 10 the physical disk failed, and at same period disk 11 became "bypassed". Global hotspare at slot 20 is in use now which is sparing the bypassed disk at 11 (As seen in the Recovery Guru). The disk group status is "Degraded". Physical disk 10 SAA is "Yes" and that of 11 is "No". At this point we replaced the disk at 10 and it became optimal after some time and the disk group status also became optimal, but the bypassed disk (11) remained in that state. Now 10 is mirrored pair with 20 (global hot spare) and 20 is still showing sparing for disk at 11. Is it safe to replace 11 (bypassed disk) ? The Service action (removal) allowed status of disk 11 is still "No" which is confusing.  Please help. Attaching some screen shots which might help.
Disk in bypassed state and SAA "No"