I'm on a non-B visa with work permit, but I'm having a baby at the beginning of July (well, whenever he decides to come out really), which is also when my next 90-day border hop is due. I'm told that I can get a doctor's certificate to say that I cannot travel when I should be doing the border hop and get an extension of stay without leaving the country.

I was wondering if I got the doc's certificate in May and went to immigration, would they give me the extension that much ahead of time? Not only would it be nice to have it done early in case the bub does decide to come early but also my WP is due for renewal at the end of May and I'm sure they'll only give me a month on it (until the current expiry date of my entry stamp) if I don't get the extension before that.

Anyone know if they'd issue the extension over a month in advance?

Are you on a multi entry B visa? you can make a border run at any time. It does not have to be at the end of 90 days, it can be whenever you want, and you will get 90 more days. So you could make a border run middle of may, 6 weeks before your planned due date, and that should give you until around 6 weeks after your due date before you need to make another.

Yes, I know, but I really would rather not sit in a minibus for a day at nearly 8 months pregnant and flying is out of the question after May 25th. That was what I was going to do originally but then I heard that I can be excused on medical grounds and would much prefer to skip a trip altogether if possible.