There are loads of different coloured overlays, and children with specific need for them (with certain visual difficulties and specific types of dyslexia) should be tested by someone who knows what they are doing, in order to find the overlay that actually helps (schools seem to love them and ime bung any old colour they have at a child, or let the child choose!)
I would want to talk to the teacher about why they used it? Do they feel your dd needs further testing and do they have any concerns?
She doesn't say much. She's been quite slow to read but she has a lazy eye and wears glasses. They had a bit of a sudden Interest in her diagnosis after it became clear shed fail the phonics screening but after realising there was nothing they could put her on the register with things died down
When ds was in year 3 at school they all got tested by an optometrist for irlen syndrome, ds now has an aqua overlay and says it helps a lot, he isnt dyslexic and his reading ability was above average.
Wow didn't realise it was quite so complicated. It's parents evening very soon I will ask teacher then it may just be a one off. Got another eye appointment coming up soon then so can perhaps ask about lenses then