According to all the info I have, there was no rain. Only thing I can imagine is that there was some temperature drop as they start actually ca 2 h later (in the morning it was 2 h and 7 min later, so the last stage should have started at around 19:27) and there were some interruptions in the stage as well (maybe even later then). So, they might have started even later. also the light starts to drop later on (many forest sections on last stage). Finally, Evans and Neuville are running Hankook like Virves, they have only hard and soft option (+ wet). When ground is cooling, I don't know how these tires react, definitely the WRC tires are more for durability than performance.