We had planned our stay in Airlie Beach 2 months before getting there, and we booked by email with Illusions. In my email I asked what was needed to confirm the booking, and they replied that my booking was confirmed for November 10 and nothing specific was needed (ie no upfront payment).
One week before the trip they sent me an email to know in which hotel I would be staying to plan a pick-up. I replied and asked what time would be the pick-up.
The day before the trip, I tried to reach them several times to know at what time I should expect them but no answer. I asked my hotel if they could call them, they let a voice mail but they never called back. In the evening around 7pm I succeeded to join them on their cell phone, I asked for the pick-up, and the girl over the phone checked my name and said that MY trip has been CANCELLED (understand my trip not the trip). I said that it must be a mistake because my trip has been confirmed long ago. But the girl confirmed what she just said, and that I couldn't change anthing, I told them that this behaviour was really miserable if I hadn't called I would have not known, and that knowing that after 7pm means the next day is screwed, if they wanted me to pay before they should have let me know in the first place. But the girl hung up saying sorry.
As a matter of fact, we cannot trust illusions.
Luckily enough, I found a trip agency open on that night which found us a spot on Derwent Hunter, which does almost the same thing in a bigger and nicer boat. (you should compare the websites).