Mark,
Of course, people may grumble about the date being unsuitable, but you can't please all the people all the time,
This is true. And of course no date will suit everyone - it's one of the perennial problems of co-operative working. The important thing is not to choose a date when almost no-one will come.
So unless there is an avalanche of interested people stating that it doesn't suit but that they would come if it was on another date, let's fix it for the 17th and see what happens.
If it's a success on all sides then there is no reason not to repeat it in the summer - if not then not :)
Syd