Upgrades on Friday or Saturday

I'm planning to upgrade aprs.fi on either Friday evening (30 Oct 2009 around 1500z) or Saturday morning (31 Oct 2009 around 0700z). I'll be reconfiguring the service to use a completely different web server software than before, so there will be an outage of some sort. If everything goes well, it won't be more than a few minutes. There might be some surprises on the way, since I don't have a proper lab setup to run the new configuration with a simulated heavy load.