here is the email I got from LVO after submitting additional supporting documents voluntarily. However, it is an automatic reply but at least they have replied right away, and its been 3 weeks alreay and I didn't get even a single email from ISD after submitting documents to them.
Original Message to LDN (IMMIGRATION)
The London visa office has received your email. We’ll reply within 28 days. Don’t resend your enquiry. We reply first to emails we consider urgent where the urgency is stated clearly. We only reply to case status enquiries if the processing time shown on UnitedKingdom.gc.ca (not cic.gc.ca) has passed. If you’ve submitted new information, we’ll update your file without replying.