H1b Dropbox process for consulate in Canada

Hello folks! I was wondering if anyone is aware of what the Dropbox process for H1B visa stamping is, if you apply to a US consulate in Canada. I googled this, and kinda saw some forums that made me think some people mailed their documents to the consulate and got it stamped, instead of having to go in person for the Dropbox. Is this at all possible? Also, for in person drops, what does the turnaround time look like (planning to stay at an Airbnb for the duration)? Thanks in advance!