Ars have it wrong too in that case!
The name was invented, as I said, on TheWeatherOutlook forum around 2001. It then spread to the other weather forums (NetWeather, UKWW, even uk.sci.weather) in the UK.
The media, then, picked up on it in 2018 and ran with it - it's catchy, after all. You then get places like Ars bastardising the name as they don't know where it came from in the first place.
FWIW, the primary driver of the Beast in 2018 was actually SSW which occurred a few weeks earlier.... much as was the case this year, which also saw an easterly with snow. This year was actually the first midwinter easterly since 1997, the 2018 event coming right at the end of winter (in late February, spring starts on the 1st March). Before 1997, we had them in 1996, 1993, 1991, 1987, 1986, 1985....
Needless to say those of us who like snow and cold in winter are hoping the miserable run of snowless winters is coming to an end!