rshdunlop - not to be too intrusive, but as I said before I have been very impressed by the HH3's range and its three dimensional capability. When it has been installed as a replacement for an HH2 in a three storey house, it has reached all the blindspots the HH2 could not reach (does this sound like one of those old beer adverts?) and on all three floors.

It may be worth experimenting and try to connect at least some of your devices directly to the HH3 using wi-fi.

Incrementally, if they all connect, you may not need the extender at all. Alternatively you may find that the number of devices that need to connect via the extender is reduced.

On a note that is a little too technical for here, you could ensure that the extender is configured in such a way that all DHCP functions are being managed by the HH3. This would mean that clear downs on disconnection are being managed by the HH3 and is not getting confused between the HH3 and the extender.

Trust this helps.