Please recommend a Linux SBC with Industrial stability while it is made in ABC?

Border router has a special meaning, I doubt that's what you actually want (if you are, then a typical SBC is going to be very inadequate).

There are ready-made, packaged, small edge compute devices, some of which are intended for industrial deployments. You'd be better off using one of those, even tearing them apart and repackaging them if necessary (some industrial users tend to do that), since they usually run Linux under the hood, and many of the modern ones will allow you to run either a container or perhaps a full virtual machine with your software.

Otherwise, another option is to get a custom SBC made to your specs. Raspberry Pi and/or Avnet offer this service. An example is a Hilscher product called netPi, it's an industrial device with custom Pi in it, although it was discontinued last year. However, they offer an alternative product called netFIELD: https://www.hilscher.com/products/edge-gateways-with-container-management/edge-gateways/nfx8m-d2-n32-010

You can run your own software on it, since it supports containers. I don't know if it has an LTE interface (or if it could be added as a plug-in module) but there are other ready-made devices out there with LTE.

Thanks for your valuable opinions.

Yes, you are correct because I still need a Wi-SUN border router board to connect to my Linux SBC.  So I need an industrial grade Linux SBC to work with a separate Wi-SUN border router.

I just doubt how a TI WL chip dies after 6 months of purchase?!?  It is at least 10 years!  

The most possible cause is the inferior resistors, capacitors, fake big name components, low quality China components, etc!  Just see how they pack their electrical vehicles!

I think that netFIELD has a good chance to be suitable. There are serial, and USB and Ethernet interfaces to connect additional hardware. The manufacturer rates it to +60 degrees C, but if you talk to them, they will tell you what the limiting factor is (and if it can be modified). For example, they may state that better cooling is needed to operate at +85 degrees C.

A few asks - related to industrial design:

The BPlay has no industrial certifications. Is it matching your SBC with Industrial stability requirements?

Where do TI specify the 10 years for the WL card?

Raspberry Pi make the 'Compute' module which I believe is used in various industrial-grade PLC's and the like. I don't know much about it as a) I've never had cause to use it, b) the last company I worked for made their own PLC look-alikes, and c) I havn't worked in industry for several years as I am retired. The information is on the Raspberry Pi web site, it might be worth a look. But reading between the lines it looks as if you might be needing military spec devices at vast expense, and I don't think the Compute module qualifies.

It's often things like crystal choice which can make the difference and some other components might operate at higher temperatures when tested. As well as the compute module, Avnet also offer a complete custom service (in conjunction with raspberrypi.com as I understand) where they will drop the Pi design directly onto a PCB. Hilscher did that with Avnet (I think). The photo below isn't high-quality, but the Pi 3 portion is visible at the lower-right. Since it was a custom design, they were able to add plug-in functionality, like interfaces (don't know if they had LTE, I think they didn't, but they were thinking of opening up that port so that users could create their own plug-on boards). But it's now obsolete (I think due to part obsolescence), and they suggest the netFIELD product now.

I think if the OP finds the closest industrial product that meets his needs (there are dozens of industrial computers and routers, and nearly all will support custom applications), he should talk to the manufacturer, who will probably be more than happy to advise how to further ruggedized and improve the temp spec to meet a need. If he has money to spend, then Avnet will design him one based on a Pi.

Yes, I am locking down to Pi Compute IO Board and AVNET MAXX Board which claims to work between 0C to 70C.

hk.element14.com/.../4551378

However, MAXX Board is also made in China, a big alert of low quality! (hidden issues are - recycled components, fake big name components, low quality China components with fake specifications claimed, etc).

I am not making anything military.  I just hope my electronic can tolerate outdoor weather around a year, similar to most outdoor communication gears.  First of all, I want to try my gear in East Asia.  So 0C to 70C, somewhat humid around spring and summer, should be reasonable.  Also, we must consider those super hot sunny days!  The Sun is not kidding nowadays.

These are my experiences on my own electronics:

• I did a test on my China smart phone.  I placed it inside my refrigerator. I closed the door.  A few minutes later when I took it out, it hung.  Refrigerator is at 4C.
  
  
• My 2 Japan made Toshiba water kettles.  It boils water up to 100C everyday and keeps warms with built-in electronics.  In winter when the temperature is close to 0C, it still works.  I own 2 of them.  Each works almost 10 years.  The first one was dumped because my family complained that it's appearance was too old.    They meet industrial standard.
  
  
• My Philips rice cooker.  it boils con-gee, rices, everything we feed into it up to 100C everyday and still works after many years.  It is industrial standard.
  
  
• My Mitsubishi consumer grade refrigerator.  It works from -20C (freezer) up to very hot summer 45C (its case?!).
  
  
• My Japan made rechargeable NiMH battery.  I charged it one time and it has been driving my blood pressure meter so many times.  I even forget when I charged it last time. 
  
  
• China made rechargeable NiMH battery bought from RS.  After several times of use, it could not drive my blood pressure meter any more.  I could not even recharge it successfully.  Then, I dumped it.    Its price is the same as my Japan made rechargeable NiMH battery.
  
  
• China made RS electrical wall plate - I screwed it and it broke.  My family scolded me and I replaced it with a Britain made MK electrical wall plate.  I screwed it hard and it is still intact.
  
  
• unknown dimmable wall switch + ikea dimmable LED light bulbs - users complained that ikea bulbs burn once each day and they must keep the bulbs on to keep them alive.
  
  
• French made Clipsal dimmable wall switch + ikea dimmable LED light bulbs -  I have 4 of them and they are still working after one and 1/2 years.  
  
  
• My 3 Panasonic air coolers - one runs 20 hours a day in summer and still runs after 12 years.  I even can't touch its metal case in summer.  In addition, I keep them clean with expensive 3M air filters.
  
  
• my China made blood pressure meter readings deviates from an in-hospital blood pressure meter very much.  My Japan made AND meter matches with hospital blood pressure meter very well.
  
  
• My 2nd handed DELL PC runs for 2 years in my living room.  I just shut it down for cleaning up in winter.  In summer, its case fan roars and still works.

The experiments go on everyday.

Thanks for that nice photo.

I am also considering something like this after having read your comments.

I will start with Pi Compute IO Board and AVNET MAXX Board.  

I also think that a grounded metal case is crucial for stability.

We used the PI CM4 module. It has the best support and you can be sure of ongoing updates. Some of the other systems we used needed "Custom" linux. That was out of date or hard to compile