Past Perfect using for and since

[Dea000]

How do you turn this question in the past perfect by using for or since?
I was in China in January.

[TheParser]

***** NOT A TEACHER *****

Maybe something like:

I had been in China since January when my boss called me on March 1 to order my immediate return to New York, where

I would take over as the CEO of our company -- with an annual salary of $10,000,000 + a mansion (with 10 servants) in the

suburbs + five fancy automobiles (each with a different chauffeur).