Safety rating changed despite no recent races

Following the latest update I didn’t play multiplayer until sat 14th Dec.
Safety rating dropped down to E. 2 days previous to update was the last time I played multiplayer and was at A.
Why?

*I intentionally used past tense

Hi,

Was B, I drove 4 clean races. Last one 0.50 sec for off track mistake and dropped to E after. Seriously?