Watch the first minute for added relevance...
Arena and Rated Battleground Season 12 is scheduled to end on Tuesday, March 5. From this piece of information we can surmise one of two things:
5.2 is due March 5th (US) OR
5.2 is due March 12th (US)
Considering the previous post on having enough time before the patch to earn 3000 Valor points was last week, I think it's fair to assume we now have a fortnight before everything changes. Therefore we'll see 5.2 on March 5th.
You may now return to panicky behaviour as you realise that you still won't get everything done you want in time.