In https://squareup.com/help/us/en/article/7237-stock-conversion-sell-by it shows an example of stock conversion but is it also possible to have a conversion from bottle to 2 different glass sizes? Square does not accept two different Glass SKU's for the same stock item.
This should be possible by doing the same steps and creating 2 different size Glasses.
I can Sell candles by Single unit, Case of 36, case of 12 or half case of 6. So for you, if you set up that it takes 4 - 8oz glasses to take from 1 bottle and also or 2-16oz glasses = 1 Bottle that should work for you when you create your new units. You would just need to make more units and specify the sizes instead of just having " Glass", you would need 8oz Glass or 16oz Glass or small and large etc.
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