Yes, pred fail  1:1 is not actually offline yet, so hot-spare can't rebuild. You need to force 1:1 offline first, then hot-spare will begin rebuilding automatically.
Hello,  This is my situation  RAID5 ARRAY  T420  PRECH710 Physical Disk 0:1:0 Online Spun Up Physical Disk 0:1:1 Online Spun Up Failure Predicted Physical Disk 0:1:2 Online Spun Up Physical Disk 0:1:4 Ready Spun Up GLOBAL HOT SPARE Physical Disk 0:1:5 Online Spun Up  What do I need to do ? execute  -OFF -  Physical Disk 0:1:1 then I will see rebuild option to execute on  Physical Disk 0:1:4  ?   I don`t sure because the OPEN MANAGE send me alert  "Making a physical disk offline may result in data loss. Are you sure you want to offline this physical disk?" When I trying to execute  -OFF -  Physical Disk 0:1:1  HELP    
Failure Predicted instruction