IP address changed

So I recently set up a DDNS service to be be able to use https://hetrixtools.com/ and/or https://www.thinkbroadband.com/broadband/monitoring/quality free services. The idea of using DDNS for these is I don't have to reconfigure them if my IP address changes. Reading past posts it seems IP addresses rarely change despite being on Virgin's consumer service. However just a few days after setting this up I see my IP address did change just before midnight last night! System Uptime on the Hub 3 is reported as > 20 days so I don't think it rebooted or updated last night. Maybe there was some kind of network upgrade?

Anyway this caused Hetrixtools to notify me of down time (false positive) whilst the DDNS service sorted itself out and the IP change propagated. I don't know if my service was actually interrupted at that time, but certainly Hetrixtools couldn't ping my Hub from a number of locations to its original IP address.

Hetrixtools is doing its job, but anyone have any idea if this is a 'one off' or if Virgin are now changing dynamic IPs more frequently? Perversely, whilst many folk like gamers want their IP address to change frequently or on-demand, I don't as it causes these false positives 🙂