Kittens itchy and scabby around ears and eyes

[WillyWasAWatchdog]

We got our two kittens when they were about 12 weeks old from a local rescue centre, they were ferals so were riddled with ticks and worms when they were found at about 7 weeks old but seemed healthy when we got them and had passed vet health checks etc.

They are now about 16 weeks old and coming on really well except over the last couple of weeks they have both developed itchy patches above their eyes and around their ears which have now gone dry, flaky and scabby.

The vet says there's nothing inside their ears and eyes are fine too, he thinks it's a flea allergy but they have both been de-flead and wormed 3 times since they were rescued with vet prescribed treatment. Also why would a flea allergy only affect them around their eyes and ears? The lady at the rescue place said one other cat has exactly the same symptoms.

Has anyone seen anything like this before?

[WillyWasAWatchdog]

Forgot to mention the vet has given us some antiseptic wash to bathe their sore bits which is helping but new itchy / bald patches seem to be appearing on their heads / back of ears