I happened to see the 2016 printed catalogue for this company at a friend's house. Their 0844 number is given in  many places without any indication of charges.

The home page of their website doesn't give any indication of charges either. https://www.celticandco.com/
Their contacts page https://www.celticandco.com/ does give acceptable 01 and 03 numbers but their statement of charges is totally wrong.

Since they themselves give 01637 871 605 as an alternative number I think it should be promoted from "unverified" to "main" in the SayNo database.

I've not dealt with them and am unlikely to do so. Are their errors due to ignorance or deliberate policy? Who knows.