Congrats...and very interesting.
This is one of the earliest 165.024
BT's I've ever seen. "Normally" in this serial range/production months (2379x / summer 66), we see a 12 o'clock marker dial, stick hands and type 2 bezel, but also yours type 3.
And subreference 165.024-
64.
Just like my serial 2379x, 165.024-64 below left (with type 1 bezel right now, but did came to me with the type 2). Mine also with a 1506/16 bracelet.
Anyway, "normal" assumption on the BT dial, is that it was introduced along with/after the W10 military version in 1967 and finally with the RN300 official MoD specs in 67/68 and then in the same year (late 67, early 68) introduced into the civilian versions.
So, perhaps yours was a pre-run, or parts were exchanged at service... or the above "normal" assumptions are just wrong in this case /the transitional period started earlier and lasted longer ;-)
Would be interesting to know if the caseback on your's is a straight 165.024 without subreference or a 165.024-64??
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