This is certainly an interesting variant, and one which I have not seen before. It's interesting to note that the "L" character matches the colour of the middle bar.
Here are two examples of the POM markings painted onto items in my collection. The first one appears on the lid of one my Lantern Crates which was retrieved from Falaise:
Unfortunately, I don't know of any more information about the unit, and as far as I can tell, there are no other indications of unit markings on the Crate itself.
This second example has been taken from a Large Blanket Set Case. This particular was purchased in Normandy about 4 years ago, and so once again it's unlikely that it ever returned to the US. The seller had a couple of other examples which he was keeping for his personal collection, which featured in a number of locations the word "OMAHA", whether this indicates the destination, one cannot say for certain:
In addition, the following marking appears on both ends of the Case:
And this on the bottom:
Which reads "GLUE G MED II SA 205 ADV". If anyone can provide any additional information about these markings, kindly let me know.
Also, please feel free to share with us any items from your collection which bear these POM markings...