What do we know about these for non-chronograph UG watches?
I note that the latest Railrouter appearing on the ebay thread has on the caseback 2385347 giving it a production date in the 1963/65 period and a second (case reference?) number 585100.
In addition I have recorded the following numbers on Railrouters:
412501/1
865100/02 2825468
885100 2855343
Something else for the database?

 

I'm not sure we know much at all about case reference numbers for non-chronographs.

As I understand it, the table of case reference numbers that we all rely upon from Sala was deduced based on chronographs from the 1940s and 1950s in the archive records.

There is therefore no reason why the table should apply to later watches or to non-chronographs.

Another reason why an online UG reference guide would be so useful.

 

If it's simply a matter of amassing enough examples to discern patterns in the numbers and from those patterns attributing meaning, it might not be so hard to figure out what the case reference numbers actually refer to, particularly if data is pooled.

Here are a few examples; an FS watch (picture pinched from ebay), a catalogue page showing a Polerouter Electric ('borrowed' from a post by gop76 - thanks ), a Polerouter Super (mine), and a shot of the caseback of a Railrouter.









The numbers of these watches are 864107, 860100, 869112 and 865100. All are stainless and all share the same initial reference number, 8.
The polerouter electric is also available in solid gold with the reference 160100. Gold plated railrouters have references beginning with 5 (examples below are one recently sold on ebay and a 'nos' case from my parts drawer).





All of this seems to infer that the first number relates to case material.
The second and third numbers I think might relate to the movements; note that the FS is a cal. 64 (ref 864107). The polerouter electric uses the ug. 60 movement (ref 860100). Railrouters are known to come with either the cal. 1205 or cal. 65. The Super is a Cal. 69
Subsequent numbers could relate to the design of the case itself, though unfortunately, with such a small sample size (all from the 60s), this is harder to ascertain. It is, however, interesting to note that the Polerouter Electric and Railrouter case ref's end with 100 and have very similar case designs.
As ever, take all of this with a pinch of salt - it could well be piffle

 

Thanks rustynuts. I probably misread 6 for 8 in the examples I listed for Railrouters and an amended list, with " //" interpolated and retaining the original "/" would be
5//65//100
4//1250//1/1
8//65//100
8//65//100/02
This would seem to confirm that the second set of numbers identifies the movement but I'm puzzled by the 4 in my 2nd example. I'll have to check my records.