Originally Posted by Adam1222

that is not the eligibility or name of rate.
There should be a name of the rate and it may include eligibility conditions. Unfortunately, I checked the NPR code for London properties for a random date in November, and some have eligibility conditions and some do not, examples below. If it is an Entertainment Rate or BCD Entertainment Rate, you risk being asked for proof of affiliation with either BCD Entertainment travel or the entertainment industry.
(A lot of people mistakenly thing this code refers to what used to be called the Entertainment Book in the US, but it does not. BCD Entertainment travel is a company that specializes in making travel arrangements for TV/movie industry, etc.)