An offer to help

is not something I give lightly. Middle Cat is much more "spur of the moment" about such things than I am.
I suppose I have always been rather cautious about such things. I tend to be uncertain about whether I will really be welcome.  If I offer to do something I know, because I will have thought about it, that I can do it. Of course that excludes the same circumstances that would exclude anyone else but, apart from that, I have thought about it. 
I think about things like where an activity is going to be held and how I am going to get there as well as what is required of those  involved. I think about how much time is likely to be involved and much more. 
No, it isn't that I spend a lot of time contemplating these things but they do pass through my small feline brain before I put my paw up.
So some weeks ago I volunteered to help with something. It is just for a few hours this week. I did it because I am not preparing for a big Christmas lunch or dinner. I knew the weather was likely to be hot and the other likely volunteers would be older than I am. 
As it turns out the weather is going to very hot. Middle Cat told me she would take me to the venue...a few minutes in the car but a good twenty-five on the trike. I could also stay a little longer than I had originally planned if it would help the person running the event.
There was an email from the organiser to the  helpers...she is a well organised person and gets things done. I emailed back and offered the extra time if she needed it. 
The response has left me puzzled. It was a "thanks for offering to help...if the others can't get there I will let you know". Does the organiser want me to help or not? I had assumed from the first email that I was needed at least part of the time. Now I am not sure I am needed at all. I emailed back and I am waiting for an answer.
But it has made me think about other volunteers as well. All too often we hear the words, "It's always the same few people who volunteer".  I know that's true. Some people never volunteer and others do so only reluctantly or have to be asked to help. But, if we do want people to volunteer, then it seems to me that it needs to be made very clear they are wanted and what they are expected to do.  They also need to be thanked once the job is done.