When only 1 day remains on the membership, it'd be more helpful to show hours remaining instead of 1 day.
I am almost certain that your statement is not true. As far as I know x-days membership ends exactly after x*24 hours. I think that VermillionOcean's suggestion is a good one and should be implemented.
It ends at whatever time of day you bought your membership - it's easier to remember when it's due to expire now with the 7 day memberships. I quite like @VermillionOcean 's suggestion as well.
Pretty sure this is correct. I like the suggestion, too, but don't know how easy it would be for @Jon to implement.
I remember buying it just a bit before 8pm (which is the reset time for me). My membership ended at around 3pm today, so I'm pretty sure server downtime is added on top of the membership time, which is pretty standard practice for most MMOs with time duration stuff out there (unless I'm misremembering when I bought it...). In any case, it definitely does not end at reset time.