PHP Parsing code

If you are not signed up to this page https://www.innerdrive.co.uk/resources/ then this page https://info.innerdrive.co.uk/subscriber displays rich text values of NOTSUBSCRIBED. When you are signed up then the page displays values of SUBSCRIBED.

I have tried various parsers and can only get the value from the page https://info.innerdrive.co.uk/subscriber of NOTSUBSCITBED even when the page is a normal browser is clearly displaying SUBSCRIBED (because I have subscribed)

I need a PHP code snippet that parses the page https://info.innerdrive.co.uk/subscriber and returns a value of SUBSCRIBED when the page https://info.innerdrive.co.uk/subscriber is displaying subscribed for that user (because they are subscribed)