Schedule route by time

In the town I am in, it is impossible to have a downward GPS signal. How can I make a route schedule to be done every 2 hours that does not depend on the GPS and is guided by the waypoint in some way?
This would be used for a security monitoring rover.

There is a Wiki for that. Well, typically it’s for Indoors but some is relevant.

Try GNSS Planning for where you live.