Adding extra occurrences when editing the repeats

Hi,

When editing the individual events is it possible to add extra occurrences?

I have set up a series of repeat events where I have then edited each individual occurrence. One example is where I have an event at various locations that I added initially setting up a regular event and then editing each occurrence with the location for each repeat. Now they want to add an extra date to this. I cannot see a way of doing this other than updating the main event but then I loose all the individual edits.