I just started using PBS Postage with DC today.  My return address is my home, but I've been dropping my book packages at work, which is easier than me going to the PO.  Will this be OK?  The zip codes are different.  The wrapper says "ships from xxxxx" (zip code) so wanted to be sure.

I haven't had a problem in the past using regular stamps this way, but realize things could be different now that the package is scanned. 

I also have to be sure my work mail goes out in time for the date on the package to be correct. 

not a problem at all.  now I know there is something about the PO that it is dropped off getting credit for processing it, but if dropping it off at work is easier then don't sweat it.

I use PBS postage and  mail from a different post office zip code all the time. I was worried about that at first, but so far, so good!