It is preferable to have a single pool on a Compellent but if you HAD to do 2 pools, to switch a volume from one pool to another, you would use the built in Copy/Mirror/Migrate process which will auto fully copy the LUN from one pool to the other and then it will remap the LUN on the host for you and it can be done live.
Is it possible to migrate/move a LUN between Storage Pools? So my scenario would be 2 storage pools, Pool A and Pool B.  I have LUN 1 in Pool A and I want to move it to Pool B.  If so would this affect host access? Regards.
SC8000 - Migrate LUN to other Storage Pool