Ferries to Kasaoka islands in mid-Dec?

Hi,
Will the ferries from Kasaoka to Shiraishi-jima and Manabe-jima, and onto Tadotsu be running in mid-December, if so, on a normal or reduced timetable?
Is it possible to visit both islands, ie, ferry between Shiraishi-jima and Manabe-jima?
Thanks.

Will the ferries from Kasaoka to Shiraishi-jima and Manabe-jima, and onto Tadotsu be running in mid-December, if so, on a normal or reduced timetable?

There are ferries from Kasaoka to Shiraishi-jima and Manabe-jima, but I cannot find any ferries running between these islands and Tadotsu. Are you sure that such a connection (still) exists?

The ferries are running according to the regular schedule around the year.

According to Lonely Planet, there is a ferry from Manabe to Sanagi-jima on Tuesday, Thursday and Saturday, where transfer is available to Tadotsu.

I was able to confirm the ferry between Manabe-jima and Sanagi-jima. It runs on Thursdays and Saturdays only.

thanks Uji.