Hmm I know of an office tower proposal but unfortunately I am not at liberty to disclose info at this point. But this is not it.
Crunching these numbers backwards gives us the following. If we assume an fsr of 10 which would be standard on anything this size means we are looking for a parcel of land that is 400,000sqft, or 630"*630". Can't think of anything that size off the top of my head. Even if the city were to become super generous and allow a doubling of density to 20fsr we would still be looking for a parcel 630"*315" or 1260"*157". Speculate away, I'm going to go with it's part of NEFC and the heights are wrong.

But I'm willing to be proven wrong.