I'm gonna have to say no.
I did a Sienna about a month ago and it rained about an hour after I finished with EX-P. When I came back 2 weeks later to wash it, I noticed no beading, but the water just laid flat on the surface. I re-applied EX-P to rejuvinate it. That 24 hours is very critical for the bonding process. I'd say just apply another coat after your next wash.
Good Luck.