A 1970 car with a 15A paint code?

[Alaskan_TA]

Has anyone here seen a 1970 car with a paint code of 15A ? It appears to be a very bright white, but I have not seen it until today. Car in question is a 1970 Valiant. Any info such as paint name, why the code does not follow normal Chrysler paint code layout etc. would be appreciated.

Thanks,
Barry