Only posting for future researchers. A whole lot of mis-information on this forum. That doesn't do it either. That will only release/renew the IP given to that interface, not the client connected to it.  https://www.cisco.com/c/en/us/td/docs/ios/12_2...

I had to regenerate the crypto key on a 3850 after upgrading to "cat3k_caa-universalk9.SPA.03.06.06.E.152-2.E6.bin". This was unexpected. Is this a feature or a special surprise gift from Cisco? 

Worked like a charm! Thank you! *Edited* the command i had to use was slightly different "archive download-sw /overwrite /reload tftp://<IP address>/ap3g2-k9w8-tar.152-4.JB5.tar"