In my email, I explained about the forum and that I received info via other applicants on how to upgrade. I didn't want to barge in and demand an update on my application status because that's counterproductive at this point, so instead I provided a few factual observations and then asked if it was worth upgrading and what would be the estimated time difference. If you are thorough and ask DIRECT questions, they'll give you direct answers. If you keep emailing them just asking for an update they can't do anything for you because they're not the ones physically holding your application anymore.
Additionally, when I first applied they sent me an email saying I forgot a document and that when I fill it out and email it back to use a certain code in my reply field (it's individualized so I can't share it), but that's how they decipher between emails that pertain to pending applications and general inquiries. If you were missing CRITICAL documents, they would've told you as soon as it arrived. I'm sorry I forgot to mention this earlier, but if they need something from you they would've asked you when it was first opened or they will come looking for you while they're reviewing it. These days, 99% of things can be emailed. I'd like to believe that they are logical folks who would not deny your visa if they needed a copy of something you could email them in 90 seconds.