[Q] Cannot access UMTS or service menu topic

I'm trying to get to the service menu to get to UMTS to remove the carrier lock but entering *#197328640# does not work, would downgrading my firmware to 4.3 get this option back? or is the service menu still avable (hidden)

Note 3 N9500LTE locked to EE (UK) stock unrooted on 4.4.2 base N9005XXUGNG1