Cache time comes from the origin/site HSTS header.

This is set with something like

Strict-Transport-Security: max-age=16070400; includeSubDomains

This setting will continue to pass the HSTS header, unless it is disabled.

To disable HSTS for clients and wipe out their redirects use

Strict-Transport-Security: max-age=0

Specifying a zero time duration signals the UA to delete the HSTS Policy (including any asserted includeSubDomains directive) for that HSTS Host.

Error code: ssl_error_bad_cert_domain.

If you see “I understand the risks”, follow these instructions. Otherwise:

• Close all tabs open with the site.

• Clear your history.

• In the address bar, type about:permissions.

• Search for and click on the site.

• Click “Forget About This Site”.

Error message “Cannot connect to the real <domain name>.”

• In the address bar, type

  chrome://net-internals/#hsts

• Type the domain name in the text field below “Delete domain”.

• Click the “Delete” button.

• Type the domain name in the text field below “Query domain”.

• Click the “Query” button.

• Your response should be “Not found”.

Error message “Cannot connect to the real <domain name>.”

• In the address bar, type

  chrome://net-internals/#hsts

• Type the domain name in the text field below “Delete domain”.

• Click the “Delete” button.

• Type the domain name in the text field below “Query domain”.

• Click the “Query” button.

• Your response should be “Not found”.

• Close Safari.

• Delete the ~/Library/Cookies/HSTS.plist file.

• Reopen Safari