Release a new module. If it contains substanitially more functionality, keep the backward compatible API distinct. 

Old::Module

 becomes

New::Module
New::Module::OldModCompat

[download]

Then update the old module, addind text referring to the new module, and saying that the old will receive no further maintenance work. Don't remove it.

And think very carefully about the new modules name!

In reply to Re: Changing a module's namespace on CPAN by qq
in thread Changing a module's namespace on CPAN by jacques

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