Yes, it is possible to make appropriate changes to a Bill of Right in the United Kingdom, because laws change all the time in governments all over the world. Throughout history, nations have been able to adjust their laws in order to meet their changing societies. The United Kingdom can accomplish this, too.
Technically, it is possible for changes to be made in the UK's Bill of Rights. However, just because a change is made does not mean it will be permanent because of the fact that the UK does not believe in the parliament binding its successors. This means that they do not want to put limitations on government representatives after them. So, any changes made could subsequently be reversed in time.