Katie's beginning to settle in to the new roosting arrangements. Last night I switched her roosting buddy from Christa to Edie. Things like that can make matters worse, but in this case, it made an improvement. Christa simply couldn't be bothered with Katie's flighty nonsense and very gently told her so, which Katie catastrophised. Edie has been a stoic, gentle giant. Also last night, the neighbour gently removed Katie's dressing while I held her. So that job's done too.
Until Katie's weight improves, I'll continue with all the hens going to roost together, then relocating Katie and Edie after dark. They were both eating from the feeders this morning.