Taking a lateral approach to your problem...

If I understand you correctly, you used to have a server named s1, and people mapped drives to things like \\s1\public. These days s1 has been retired (or you want to retire it), and now you have a brand new server named s2, and people should now refer to \\s2\public.

You could configure s2 to resolve the name s1 as itself, via a netbios alias. To do this you just have to create a registry entry on s2:

HKEY_Local_Machine\System\CurrentControlSet\Services\LanmanServer\Parameters

Then create a REG_SZ key named OptionalNames and set its value to "s1". If you make it a REG_MULTI_SZ instead, you could then add multiple aliases.

This will give you the breathing space you need to clean up the shares in the way you see fit (I don't think you're going to be able to do it remotely).

print@_{sort keys %_},$/if%_=split//,'= & *a?b:e\f/h^h!j+n,o@o;r$s-t%t#u'