PE43711A-Z vs. PE43711B-Z

I’m looking to find out what the “A” is calling out in p/n PE43711A-Z. When I type that part # into Digi’s website, it automatically pulls up the “B” version. The data sheet doesn’t specify this information.

From what I am able to see, it looks like the part number PE43711B-Z may be a revision of the part number PE43711A-Z as they have the same data sheet and when doing searches outside of Digi-Key, only the PE43711B-Z comes up. as for the part number lineage, the part number PE43711A-Z is a former part number for PE43711B-Z. The technical reference number is R4253748