Or shouldn’t given that they can program their land line to ring at any time they like.

this service allows fixed line telephone subscribers to program their telephone to ring at a specific time, thus providing automatic wake up service.
To program the telephone to ring at time
HH MM where,
HH means Hour in 24 hours format and MM means minutes
Press *55*HHMM#
To cancel the program
Press #55# or #55*HHMM#

( via Ethionet.et )