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I guess that depends on the required performance of the circuit. Putting the switch in series will cause the current to rail tying to force the current through the switch. Assuming the switch won't be overvoltaged, the current source could saturate and be slow returning back to CC mode. But putting the switch in parallel will divert the current to ground but there will be a small voltage present caused by the resistance of the switch and the current it's passing.
But either way will work if the requirements are not too stringent.