Having only a very small flock I wasn't aware of the problems obtaining Flubenvet powder (still have enough in the pot for one more round at least.) What happened I wonder.
Anyway, in the meanwhile, this is what I've noticed with mine:
They will stubbornly eat nothing for 2 days when given medicated pellets then give in and start eating it. My lot don't even like pellets in general, given any alternative, and I have taken to grinding them down to the size of the 5% millet I'm adding. They eat that and can't see the millet amongst the mash so don't scratch everything out looking for it.
If I could only get premix pellets (as looks likely at the moment) then it would be a choice between 2 days of no dose, while they are being stubborn, or a small dilution of millet in ground med pellets.
Warm mash also tends to go down well, of course, but doesn't last well in the coop if not eaten straight away.
I got my 60g of wormer from BHWT last time. I wonder if the BHWT vets might still have access to supplies?
P.s. 'East End' millet has a reasonable germination rate for sprouting as well and is fairly cheap in 2kg bags. Indian shopkeepers know it as 'Bajra'.