How long will the applying L1-B blanket take?

[cumtcau]

Hi Friends

One question, I think this is a special question
My company wishes to apply the L1-B blanket application( not for me, but for the company at first, then I can apply the L1-B Blanket ).

I know how much time for employee L1-B apply. But I don't know how long does the USCIS to approve the employer apply of L1-B blanket petition.

Anybody knows this? This is important for my next step plan.
Appreciated!

Regards
John