Just a thought: you might want to consider two days for DLR, regardless of crowds -- because SWGE will be open by that time and there
will be crowds, Expo or no Expo. 2 days will let you take a bit more time to see both parks (and DCA is really worth seeing, especially Cars Land at sunset and at night). If you could swing 3 days, that is the minimum we suggest here to see DLR, if you want to get a good look at the parks. We don't know yet how long it will take to get into, look at, ride something/anything in SWGE, so that could take up a significant chunk of your one day in DL. Wednesdays are generally good days, especially the morning hours. If you could be at the parks for RD on Thursday, that would give you some great time to get a lot done, too. Are you staying on site? That would give you one hour early entry to DL on Thursday. MP would help you get more done in the parks, too. Generally, past Expos haven't really increased the park crowds during the event, although attendees do visit the parks in the evenings. I don't know about the days before and after the event this year because SWGE is an unknown factor. At the last Expo, we all got to see the fabulous model and hear all the tantalizing news about the new land. Now that land will be open and all the
D23 people will want to see it for themselves. Also, Deluxe APs are allowed back into DL that week after having been blocked since mid-June -- I think this is a bigger crowd factor than Expo. All these local APs will want to see SWGE badly, and they
will visit DL.