I have a VR400 v3 router and also an RE315 Mesh range extender. The router is set up as a DHCP server to assign IP addresses in the range .1 to .99 on my local network, so that I can use addresses above this range to reserve for certain devices. When one of these devices connects directly to the router it picks up the expected fixed IP address. However, when the range extender is in use and the device connects via that, its fixed IP address reservation is ignored. Also, other devices appear to get addresses assigned that are outside the .1 to .99 range and can in some cases clash with my expected fixed address reservations.

Can anyone explain what might be happening here?