Case sensitivity depends on a value of the
FooBarBazvariable. The default value is
Offand it's strongly discouraged to change it. If you really need to do so, change it back as soon as possible.
FooBarBaz = On // Do something FooBarBaz = Off
As soon as possible sounds too harsh to me, and hence I would to replace it with something more neutral.
If you really need to do so, change it back right after.
This phrase is emotionally correct, but I'm not sure whether it's grammatically correct. I have a feeling (I'm not sure, though) that we should specify "right after what". Something like this, probably:
If you really need to do so, change it back right after you have finished your tasks.
But there are two problems here. First, I simply don't know how to say it really correct. After you have finished your tasks is nothing more than a draft.
Second, it sounds unnecessary wordy.