More often than not I come across a sentence structure like this:
Upon arrival, I learned that she was not in the town.
But if I change it this way, does it change the meaning?
Upon arrival, I came to know that she was not in the town.
Furthermore, as oerkelens came up with a good point (more common?)
Upon arrival, I found out that she was not in the town.
Is learn preferred if it's news? Or something which is noesis? I thought of several examples and could replace learned with came to know in almost all cases (of course, except learned a lesson). Is there any instance wherein "I learned that..." cannot be replaced by "I came to know that..."
My understanding: As I said, I think learn is more common when it's news that you did not expect. On the other hand, I came to know is less surprising and subconsciously known to us as a second option. Furthermore, I found out... is something that comes after you putting some efforts.
Having said this, If you learn that she's not in the town, it's the news and bit surprising whereas If you come to know that she's not in the town, it's okay without any surprising element. You, though subconsciously, knew the possibility of the second option of her being not in the town. If you found out that she's not in the town, you made some efforts to learn/know the news.
Note: I'm particular about putting the word that in the sentences in question. Or else, I learned... and I came to know... are two different things, it's clear to me.