Carbonation and pressure arithmetic
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The arithmetic behind whether a bottle survives, expressed in the three quantities that interact.
Volumes, pressure and temperature
Carbonation is measured in volumes: volumes of gas dissolved per volume of liquid.
For a given carbonation, the pressure in a sealed bottle depends on temperature, and it rises steeply.
Which is the relationship this whole page exists to state: the same drink is at a much higher pressure warm than cold, and nothing about the liquid changed.
So a carbonation specification is meaningless without a temperature, and a container choice is meaningless without the warmest temperature the product will see.
Setting a carbonation level
Pick the volumes you want from the style: lightly sparkling around 2, a typical soft drink 3 to 4.
Carbonate cold, because gas dissolves far better cold, and apply the pressure that corresponds to those volumes at your working temperature from a carbonation chart.
Then calculate the pressure that carbonation implies at 30 degrees, which is your transport case, and check it against the container's rating.
Estimating what a ferment will add
The number that matters for a live product.
Residual fermentable sugar converts to roughly equal parts alcohol and carbon dioxide by fermentation, so the sugar left in the bottle is a direct measure of how much additional gas is available.
Which means a drier product has less pressure headroom to consume, and a sweeter one has more, and the Brix at bottling is the input to the estimate.
Treat any calculation as an indication and the warm-hold test as the answer.
Choosing the container against the worst case
Total pressure equals what you carbonated plus what the ferment will add, at the warmest realistic temperature, at the end of shelf life.
Specify the container against that number with margin, ask the supplier for the rating rather than inferring it, and then test it: bottles held warm for the full shelf life, opened behind a screen.