Yes, I would recommend switching. We had 5 day park hoppers and had 2 half days of heavy rain. DCA was great for staying dry, but only for half a day and on lower priority activities (walked on Monsters inc, guardians, then spent a long morning doing turtle talk, animation academy, Anna aNd Elsa meet and greet). Luckily for us, the sun came out and we spent most of the afternoon enjoying low crowds at DCA.
Had it kept raining though, or we were only doing one day at DCA, it would not have been ideal. We had wanted to go on all of our favourites at DCA again on our last afternoon, but it started raining and rides kept intermittently closing…got soaked running over to RSR a few times, only to have it reclose. Ended up with lots of any time FP’s at DCA, but nowhere to use them. Rode toy story multiple times and soarin on the way out, but the afternoon was a bust. Moved to DL and found a lot more to do for the rest of the day.
Best of luck. Hopefully no matter which park you end up at, it ends up being only part of the day…that’s actually a best case scenario in some ways, and we found the parks super empty on a sunny afternoon while it rained all morning.