Hi there,
I've only used extended bolus for when I've been to the cinema and eaten popcorn. It worked really well, as I worked out the carbs for the whole amount of popcorn but as I would be eating it slowly over say, 90 mins, I extended the bolus to last that long. So it was trickling in as I was eating. I haven't used it since but guess it would be good at a buffet if you knew roughly how much you were going to be having.
I use multi-wave for all my meals, but only over 15 mins to avoid the whole lot going in at once therefore protecting my site. What do you eat to warrant doing it over 6 hours?! It's maybe why you're going low at 1am as your meal would be well and truly over (unless you're eating very fatty food every night for example) but you're still having bolus insulin going in on top of your basal.
As for moving abroad I'm sorry I'm not sure. I'm sure someone will be able to answer that one.
Hope you get on ok. Take care.
Jo