[idiotsecant]

If your application is so critical that NTP timing loss causes disaster and your holdover fails in less than a day and you aren't generating your own via gps, you are incompetent, full stop

[geerlingguy]

And if things are that critical, you might have other references besides just GPS...

[throw0101c]

E.g.,

* https://www.meinbergglobal.com/english/products/