There are phrases we use so casually and confidently that it never really crosses our mind that we could be speaking incorrectly, or perhaps, we could not be understood internationally in general and by native speakers in specific.
So you receive a call when you are guzzling down chilled beer on a hot sunny beach somewhere in Goa. It is your customer on the line asking when his consignment would be delivered. Trying hard to not sound drunk you mutter, “Sir, actually, I am out of station. I will check and call you right back.”
This ‘out of station’ is an example of the kind of phrases I was referring to earlier. Although this one does not entirely fall under the ‘incorrect usage’ category (some do), it is still very archaic. It was very much in use in the times of the British rule when officers were posted at ‘stations’ and so when someone called to speak to them, they were told they are out of station. Indians who learnt English back then probably just caught on but the colonial hangover clearly continues till date. Not any more though because you read it here, didn’t you?
Even though this ‘out of station’ phrase is perfectly understood in India, there is no guarantee it could be the case internationally. And it will surely come across as weird. ‘I am traveling’, ‘I am out of town’, ‘I am away’ or simply ‘I am not in NAME OF CITY’ are surely better option.