From what I have seen, somewhere in 1956 they switched over to the new design. I have a blue traveler dated 1956 as well (I think early-to-mid 1956 SN but need to check). This new decal package and paint setup switch appears to be a lot less defined than other similar transitions in decal/paint/component setups. In 1956 I see a lot of both–just my observation.
The color is somewhat rare, but I have seen at least 5 of these pop up for sale over the past 3-4 years. I see a ton of the black ones and rarely see the blue ones.
@s1b picked one of these up not too long ago (second image). Third image is another one I saw for sale a while back. Not great pics but here is a
1955 violet (probably a late '55 SN stamped frame)(Also
owned by a CABE'er at one point). Fourth pic, I randomly found this 1956, but no information on it.
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