I'm getting ready to bottle my California common beer that fermented at 55F. I see that the temperature affects the size of sugar. All the other beers I did were at 68-70 F and then stored at the same temp... now this one is at 55F but will be stored with the other ones at 68-70. Does that affect the amount or it's the temperature at the moment of bottling that matters.
It's the temperature at time of bottling that matters, so that's the temperature to use for your priming sugar calculation. The reason is that there will already be CO2 dissolved in your beer; the amount is determined by the temperature.