Goofs

The women of the choir did the singing while sitting down because of having to work in the extreme heat during the day left them exhausted.

An early night scene of the women swimming ashore (set in the week after 10 February 1942) shows the full moon. The moon was between last quarter and new moon that week.

Given that each of the women wore a single dress, day in and day out, in a tropical climate for three years straight, the fabric of their clothing would have disintegrated long before that was finally depicted in the film. Also, there's no way that the nuns would have been able to keep the white elements of their habits white, especially given the scarcity of soap.