So at least for now Vietnam has gone back to being very "chill" about people having never-ending tourist visas as long as they are prepared to go in and out of the country every 3 months. Most people use either a bus that takes all day to drive to Laos, or if you are like me, you book a flight that leaves Da Nang, goes to Bangkok, you get a Burger King, sit for a while, and then catch the very next flight back to Da Nang. It's a pain in the ass and I think everyone hates airports, but it is all done in one day. If you can deal with shitty airport wifi, I suppose you could get some work done if you have a job like I do.
Well recently, a friend of mine and I made a mistake when we waited too long to book our flights and we ended up nearly getting screwed by this process. There are only 2 flights leaving Da Nang to BKK and vice-versa every day and when we went to book our "there and back" process, there wasn't any seats available on the return flight the same day.
This was a scary moment because the E-visa process that they have in Vietnam dictates that you have a 24 hour window of opportunity to arrive once the validity of the E-visa begins. If you are just ONE DAY late, your visa is invalid and I don't even know what you do from that point forward. Probably re-apply and wait the horrific 5 days or so that it takes in order for them to process this thing that should be a very straight-forward process
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Now, I will admit that this was a very stupid decision on our part and it is particularly dumb because me and the other person that were involved used to travel for business and are very aware of the fact that flights frequently sell out, they are designed so that precisely this sort of thing will happen. Airlines don't want a bunch of empty seats, so of course they adjust the prices and size of the plane so that almost every flight is sold out.
Well we being the dumbshits that we are, we waited just 2 days before the end of our visas and then when it came time to book them, there was no option for going to and from Vietnam in the same day. We were able to find a flight leaving the next morning, but it wasn't even at the same airport. There are two airports in Bangkok and the only way we could possibly make this flight happen was to arrive at one of them, and depart at a really early time in the morning from the other. The journey between the two airports, depending on traffic, can take hours.
This was a monumental mistake on our parts and one that we will not make again.
So if you are booking visa runs in Vietnam just go ahead and book it as soon as you arrive on your original visa. You already know when your visa is going to run out and when you are going to have to leave, so why not just go ahead and get it over with?
Don't be a fool like me. I was just hours away from my E-visa being invalidated, and if that had happened, I don't even know what I would have done.