Hi,
Basic thing for doing client copy is that the source and the target system should be on the same release else you can have issues.
The new tp tools does a check and see that the source and the target is same .
But if you want to ignore it you can tick the option
But as i mentioned this will only help you to ignore the above error but you can still get error as source and target system are not on the same release further in the client import..
Thanks
Rishi Abrol