In future there might come ability to do oem unlock with imei specific passport file, but there is no info yet about which update that will come if at all.

But you can still flash back your old p17 as we are _not_ going to prevent flaghing or downgrading from rootshell. But we are trying to protect normal end user against device theft and data theft. Thats why future revocery image will query your devicelock code if that has been set.