I occasionally get the intermittent oil light coming on in my E46 and it's usually close to around the time I need to get an oil change. Per my SA, it just means that the oil level is getting lower and needs to be topped up a bit.
I don't know how accurate what he told me is but it does usually coincide with about 2k to 4k miles left to be driven before an oil change.
Also.... this is for my E46 and and that may differ slightly from your X..... just wanted to give a heads up in case
