The Breitling Watch Source Forums

I am hoping someone can shed some light on this. I have three of the newer style tang buckles...all 20mm..that are all slightly different.

The first is polished, has a raised wings logo and has A20BA.1 engraved on the underside.

The second is polished, has a raised wings logo...although it doesn't appear to be quite as crisp as the one mentioned above and no alpha-numerical code engraved on the underside.

The third is brushed, has a raised wings logo and no alpha-numerical code engraved on the underside.

Are these differences due to year of production, model of watch or strap it came on or due to something else entirely? Any help would be greatly appreciated. Thanks.