Has access to ruby to_a function been disabled

Hi I have a couple of Schemas that are a few years old but previously generating data. I went to modify one of them recently for a new requirement and found that I’m getting this error instead of data:

‘error: Access denied to method to_a.’

That’s for a formula field where I randomly generate a QLD postcode ( value from 400 to 4999) with this code :

It appears you ran into a regression. I’ve deployed a fix so your formula should work again.

Thanks that’s working again now.