The great thing about this sauce is that you can make it in advance and reheat it with virtually no effect on the taste or texture (you may actually find the taste a little richer a day or two after making it!) Keep the sauce in a sealed container in the fridge for up to 3 days.
You can also freeze leftovers for up to 3 months. Defrost thoroughly before reheating and reheat on the hob/stove over medium heat.