Anthea, The answer is very simple. There is no rule on the Internet, beyond a very small number of technical rules which are enforced only through the fact that, if you don't respect them, your computers won't be able to talk to other people's computer. So you have to send network packets in a particular format and in a particular order, but beyond that there is absolutely no control and you can do whatever you please - pull the plug without telling anyone, drop people's subscriptions, change them to the new addresses, whatever. Eric