Local and long distance calling will be unavailable during that time, along with 9-1-1 services. That includes call to and from cell phones in Cecil Lake.
Emergency services have been advised of the disruption, and residents with alarm systems have been recommended to let their service provider know.
Approximately 150 customers are affected, and have previously been communicated with.
Telus says the upgrades will improve the network to make landline and mobile phone service more reliable.