It should be 1-2 weeks. That's more than enough to pack your stuff and get out.
Of course that entails adopting first-world vote counting procedures.
How would you handle overseas ballots that can be mailed up to election day?
How would you handle provisional ballots that have to be checked against voter lists by the same people who are certifying the vote totals from regular ballots? There's actually a lot of required cross-checking of precinct data before a count is certified.
That's why it's unrealistic to do it in less than 3-4 weeks.
How does every other country in the developed world manage to count all its votes within 24 hours with virtually no errors? Well, do as they do.
I've attended the vote counting at an EU country back in 2002. They don't seem to count late mail-in ballots, if you are out of the country your vote must arrive by election day. That contrasts with the US where ballots must be postmarked by election day. That would require overseas military personnel to vote as much as three weeks before the election to insure that it arrives in time.
Provisional ballots are required to help voters who came to the wrong polling place or whose registration may have been in error cast a ballot. In the US the voter can cast a ballot and it is eventually matched up to lists at the correct precinct. What I saw in the EU was that if you weren't at the right place your vote didn't count.
The error rates in the US and EU seemed comparable controlling for the technology. My observation was that in the EU there was a greater reliance on the finality of the local count. Recounts are much harder to obtain for close elections in the EU.