I've read conflicting information. I have sent a message to someone who will know and will get back to you once he replies to my message.
I just heard from my friend Fotinos. He says "all is well". The water taxi will be running when you get there.
Unless something has changed there is no return to the tender dock by water taxi. I'm not sure why but that's the way it is. The fare for the water taxi includes a shuttle van ride up to the Oia bus square and a bus ticket you can use to get back to Fira. Once you're back in Fira you can walk the steps or take the cable car back down to the tender dock.
Thank you very much.
Hello, can the boat transfer be pre booked in advance to oia?
I was informed just yesterday by "Fotinos" that it may be possible to pre-book the water taxi to Amoudi Bay below Oia on board the cruise ships. No confirmation yet, but if you're arriving on a cruise please let us know. He did say there was an added fee for this (of course!). He also said that there was a new service from the ferry port to Amoudi Bay that would probably not be as frequent. I'm assuming that this new service will be based solely on demand and availability of the boat, since I believe they're the same ones that tender cruise ship passengers ashore.