Yes you can.
Log on to your code at the iptv66 website and you can change the server URL (s1 or s2) portal there, which is the same place where you set you MAC and/or perform an IPTV Reset.
And after changing the server portal, do perform one of those IPTV Resets
and change the URL in your receiver's setup, to match the new URL you just changed it to.