City of Plano issued the following announcement on March 30.
Ken Com resolved the issues and 911 is back up and running! Thanks Ken Com for all the hard work in getting this fixed for our residents without cell phones!!
There is a partial 911 outage at this time for those that utilize a (630)552 prefix on landlines. Ken Com is dilligently working with ATT to fix the issue. For the time being please use a cell phone to call 911. This service will be restored as soon as possible!
Original source can be found here.