It its for both new and existing customers.
Available for new and existing NOW TV customers without an active Sky Cinema or Entertainment Pass on their account. Passes auto-renew at £8.99 a month for Entertainment / £11.99 a month for Sky Cinema, unless cancelled.
To get access to this pass offer, I would recommend using Live chat.
You probably have existing passes running? You can’t get the deal if so.
And I fear it has now expired?