Thought it was a scam
Letter looks like a scam and no return address, a name with no ICO address only an expensive telephone number, this should be a free number.
Too much info (email & phone number) is being requested with the lame excuse of they may need to phone you, data minimisation principle I think not.
Exemptions form is not secure and only gets a B on the Qualys site due to poor and weak security Protocols.
You are unable to execute the form if you don't input email and phone number, thought of putting Company house email and number in.
Is it not possible to roll all this up into the Legal requirement for Annual Company House return (no email or phone number required)?