Rumour is it's close to losing the NT license due to being old as balls, but we don't have the money to renovate it, or something along those lines. It also (from a personal point of view) creates a traffic/logistics nightmare due to being close to the biggest roads in the city 
The Hristo Botev stadium is freshly renovated and in the heart of the country, it makes sense to play there, considering we're not getting a 40k crowd for nationals any time soon to be honest. Vassil Levski is still being used for Levski - CSKA and European matches for the home teams when available though.
1:1 anyway, normalcy restored.
