I think the exact meaning is not kept here. In my opinion the beginning should be like this: "Hello, sorry but Artur is not here, he is at work now, he will be in the evening..." the end is fine.
I think "he will be back in the evening" would be better. "he will be in the evening" is a letter-to-letter translation and I believe it's a polonism. Can some native speaker judge if I am right or not?