Uncommon Longines Ultra-Chron Dial - Date at 4:30, Logo at 6, French Text

Hello everyone,

I’m trying to learn more about a vintage Longines Ultra-Chron, purchased new in Greece around the late 1960s or early 1970s. Its configuration differs notably from the standard Ultra-Chron references I’ve found online.

Dial Layout:
1. At 12 o’clock, it reads: “automatic CHRONOMETRE” - note the lowercase “automatic” and uppercase “CHRONOMETRE” in French spelling.
2. At 6 o’clock, it features the Ultra-Chron logo but no “Swiss Made” text anywhere on the dial.
3. Date Window: Positioned at 4:30, which seems uncommon for this series.
4. Serial Number: 15,XXX,XXX - production likely around 1969 based on Longines’ serial database.
5. Case: Steel cushion case (not opened), likely all-original, with crown and dial intact.
6. Movement: Presumed to be Caliber 431 (36,000 bph), based on the model and period, though I have not opened the case to confirm.

I’d appreciate any help identifying the specific reference, dial variant, or production context. Here are some pictures that might help

Thanks

I think in 1969 "Swiss Made" was the standard.