Do visa days automatically reset when you exit and re-enter?

If you visa is valid for 3 months only i.e. it only covers you stay within a period of three months then the best way is to actually enter on the last day of the expiry of the visa and get 30 days to stay.   Every other entry or exit doesn't really matter as the validity of the visa itself is ticking towards expiry - but you have to leave after 30 days anyway.

I have just given a theoretical answer as I don't know the exact visa you have.  I assume you should be able to get one on arrival with Canadian passport anyway, yes?

Thanks for the quick response,

The receipt says I have a G67 3-Month Muti-entry Tourism visa. According to the officer who stamped my passport, it means I can come in and out of the country as much as I want during this 3-month window. However, my understanding is any one of these stays can't be longer than 30 days, which means I need to do a visa run on the 30th day or risk overstay fees.

My question is, does a new 30-days clock start if I leave earlier than 30 days and come back? In other words, if I leave on the 27th day and come back on the 28th, does a new 30-day ticker start or am I still on the first 30-days ticker because I didn't leave exactly on the 30th day.

Thanks again, any help would be great, again this is all within the 3-months visa timeline.

Get it now.  Yes, it will be a new 30 day ticker.  A period of stay window starts upon your entry to the Kingdom - that is the point from where the 30 days start.  The hard close is at the duration of the 3 month expiry.  As mentioned before, to maximise this, enter on the last day of the visa expiry to get your final 30 days.

That's great to hear!

Any idea on grace periods if I overstay a 30 day stretch?

Thanks again,