T6 Ocean control panel colours

[IanJD]

Hi, I'm sure there's an obvious answer to this but I've just noticed the fridge and aux heater have two colour states on the control panel buttons for aux heater and fridge whilst working. One is amber and one green, what's the difference between the two? They're working fine in both colour states and returns to red when switched off and can't find any reference in the owners manual. 2019 Cali Ocean.