Finally, most submission guidelines give you an indication of how long you may need to wait for a response. This is usually expressed as a number of months, weeks, or days (ha!).
This number serves one purpose, and one purpose only: it tells you what the absolute earliest time is that you can even consider thinking about drafting–not yet sending–an e-mail query as to the status of your submission.
The name of the game is patience. The submission process is long and tedious. To oblige you, editors give a number, so you have some idea of how much patience you will definitely need. But this number is not, I repeat not, a promise. You will receive a response when you receive a response. But if you are patient enough to wait at least the indicated amount of time, at least the editor will then at least receive your query without immediately deleting it.
Not that it will get you anywhere. For starters, query response is only slightly faster than submission response. And when you do get an answer to your query, it’s usually along the lines of: “Yes, we have it, and we’re getting around to it. Some day.”
And of course, it goes without saying that your query is always polite, humble, and non-confrontational. Your asking for information on your submission status as a personal favor, but you’re a professional, so you understand fully if they’re working through a horrible backlog.