When we do relaunch sometime we change also server and we must change DNS to point domain to new IP. It can bring some domain propagation problems. To prevent that you can use Proxy Pass.

First be sure that you have enabled install two apache modules “mod_proxy” and “mod_proxy_http”.
Then modify you vhost as follows:

SSLProxyEngine on

SetEnv proxy-sendcl 1
ProxyVia Full
ProxyPreserveHost On

ProxyPass / https://www.some-live-temporary-domain.com/
ProxyPassReverse / https://www.some-live-temporary-domain.com/