Unit 981? Should be disguised as a landscape service truck. the 700 series are mounted in the mail trucks (ever notice how you are now occasionally seeing mail trucks cruising residential streets even on Sundays?)
Saw one when we were leaving Church a couple weeks ago, cruising by the Church???
That's because the Postal Service started delivering small parcels in about February 2015, just after they eliminated overnight service for 1st class letters. That was a response to the concerns that people would have to wait longer to get their meds by mail. Many pharmacies were refilling by mail and mailing locally, so it would be delivered next day, and customer surveys had shown strong support for that, so now there are carriers out delivering those on Sunday. It was cheaper than maintaining the equipment and staffing to continue overnight local mail overall.
They deliver packages on Sundays