Rene Champagne Bottom Tanks

[antique diver]

Thanks, I'm trying to find the cut off on the champagne bottoms. I initially thought it was 11/53, but now I've been informed of 1/54 champagne bottom while I have another 1/54 showing as a round bottom so I'm looking for more 1/54 tanks to clarify which ones they were.
Do you have the serial # for that 1957 tank, I couldn't read it? I believe the month of hydro for the 1957 was May?

There's a pretty thick zinc coating over that area, and had to get the light at just right angle to read the date as 3-57 and serial #35696.

[ovalis]

Thank You!