Well, what would you say is this? I recently bought this from the very first owner, backed up with sales receipt and warranty card, sold on August 30th, 1972. Serial is a 3099xxx like yours, it came on the earliest 1171, carries a DON and has all attributes of a -69...and the caseback is a first 71, just like yours.
The lifetime owner never brought it to Omega, just once for "cleaning and oiling" to a watchmaker he kn ew, according to the marking in the caseback in 1999. And he swears he bought it exactly as it is, he never gave it out of his hands except for that one time. I had no reason not to believe this gentleman, we talked about 1 hour on the phone about the watch after I had already bought it.
So..as I stated earlier: likely this watch left Omega somewhen early 1971 with the "new" caseback or the AD had it a while in his store and pimped it to look loke the latest Model 145.022-71.
I can't tell how the caseback got on yours, but I'm quite certain this can be as it left Omega in another transition phase. We at least seem to have two examples of borderline-cases now
View attachment 407713
Click to expand...