Trying to help the In-Laws with their setup by adding a pair of P9 units to an M5 trio. Property is far from ideal, with the internet connection basically being at one end. Current setup was:

Router >(ethernet)> Main M5 Office >(wifi backhaul)> M5 Satellite Living Room >(wifi backhaul)> M5 Satellite Kitchen

Trying to add the P9s in out-buildings with the closest unit being the kitchen, but rather than connecting to the Kitchen M5 (which has decent signal in the outhouse, we get the P9 connecting direct to the Main M5 in the Office - with consequent poor signal:

Router (ethernet) Main M5 Office >(wifi backhaul)> M5 Sat Living Room >(wifi backhaul)> M5 Sat Kitchen

                           >(wifi backhaul)>

                           P9 Satellite Woodshop

The final P9 in the Barn connects ok to the first P9 via Powerline backhaul, but obviously the bandwidth is pants. Can't use Powerline backhaul from the house as it's on a separate circuit from the out-buildings. 

It seems the P9 does not have the "connection preference" functionality [yet?] so I can't force the Woodshop to connect to the Kitchen that way. Several reboots have not elicited a more sensible connection either. I can try moving the units around to just use wifi backhaul, but the final P9 is in a building 20+m from the Woodshop so I'm not sure it'll work. Any tricks to get this setup working in the one-dimensional daisy-chain I'm trying for...?