It may just be my understanding of the term "backlog."  IMO, a "backlog" is an order than could have already shipped per the customer's PO, but did not. Backlogs are different than normal production scheduling.  At least, in my world.  We have tons of orders in the system, but they are not "due" yet.

If a company like EDIG manufactures nothing, they use OEM sources.  Developing a second source for these "backlogs" makes sense.   It is not as easy as it sounds due to the engineering / tooling costs.

As for industries, backlogs (late orders) are not acceptable in the consumer products world for this reason.  Heck, for any reason. Most POs for Big Box stores are what we call "kill it or ship it" deals.  There is a short window, usually about five days, which we have to deliver to a specific distribution center.  After that, one must beg to re-window the PO to allow for the factory delay.  This I KNOW well as I have well worn knee pads. lol

John