Hi,
Is this for Richmond Hall?
I googled Cormount Partnership, and only found a couple of listings in the CRO gazette, for changes to the company articles and change of secretary.
Also found references to a 'cormount ltd' with an address in Bray, and a 'cormount properties ltd' with a London address.
Not much help really! - I'm guessing that the company might only exist for the purposes of this development.
Have you tried asking the EA for the contractor's name? Or go and have a look at the site - sometimes everyone involved plasters their name across the hoardings.