AC1200 - Xbox One has two seperate IP addresses

Hi

I've recently changed from an R7000 and moved to the AC1200. I've had a recent security scare and I'm watching my connections and log activity more than I guess I should. Anyway, when looking through my log records last night I noticed that my Xbox One is issued with an IP (192.168.0.2) and then a few seconds later switches to a new IP altogether (192.168.0.3) The MAC address is the same, as it should be, as I only have one Xbox. 

Can anybody clarify if this is just a router glitch or something else.

Many thanks

Manny.