Should I expect a letter from my Compassion child in the mail, or otherwise?

Should I expect a letter from my Compassion child in the mail? (I sent mine online; will I recieve a scan of his online, or recieve a physical copy?) Also, in my account settings I believe I've always had my preference set to receiving physical copies of high-quality scans, but last time I simply received a scan into my inbox in my account. Is that to be expected? It is completely fine but I hope to get a bit more clarification on how I will be receiving any letters. Thank you :)