By default time is set to UTC. To change it, connect to the appliance using ssh and remove and recreate the symbolic link on /etc/localtime

Ex: for Luxembourg

vc1:~ # ls -l /etc/localtime 
lrwxrwxrwx 1 root root 37 Dec  3 16:07 /etc/localtime -> /usr/share/zoneinfo/Etc/UTC
vc1:~ # rm /etc/localtime
vc1:~ # ln -s /usr/share/zoneinfo/Europe/Luxembourg /etc/localtime
vc1:~ # ls -l /etc/localtime 
lrwxrwxrwx 1 root root 37 Dec  3 16:07 /etc/localtime -> /usr/share/zoneinfo/Europe/Luxembourg