The 'EVR' at the end is the CSC network code prefix for 'EE' so your handset originated on / was supplied by EE and is running their network Firmware version. It's therefore not an unlocked device and wouldn't be eligible for the Beta programme, sorry! It will be a matter of waiting for the official release of OneUI 5 and for the EE variant Firmware being pushed out OTA.
There's a lot of confusion about the term 'unlocked'. For Beta purposes then it's not relating to a device being unlocked to take any providers SIM card (a network unlock) but actually refers to the handset's Firmware version being generic / unbranded and the device being classed as 'factory unlocked SIM Free'.