There wasn't any huge evolution going when talking about Austronesian ships. The double-hulled canoes were already swift, resilient and efficient, in other words perfect for very long journeys across the ocean. That being said we don't have enough material evidence to accurately affirm it either.

The only thing I can say is that the typology of said double-hulled canoes varies from one region to another (especially the sail) . In the near Oceania region (Indonesia/Melanesia/Micronesia) there were a lot of Amphidrome canoes (today in some isolated islands you can even found some modern canoes) and in remote Oceania (Polynesian triangle) the canoes were exclusively Monodrome.

The only witnesses we had were European navigators and their journals describing those canoes (some Navigators were admiring how efficient the canoes were compared to the European ships like James Cook) we have also the contribution of some Indigenous who travelled with Europeans like Tupaia and Omai. Other than that it's just theories and speculations helped by scientific research (Archaeology/Anthropology/History...)

We are trying to learn our culture again step by step because colonisation and Christianity happened... You know.

To give you a modern example we have the Hokule'a and the Hikianalia canoes from Hawaii, also the Fa'afaite canoe from Tahiti. Those are the best example of a modern double-hulled canoe inspired by ancient (traditional) ones. Hope it helped.