Thanks Adam. I checked and I do have the collapse by project option set for invoices. However, the report I'm talking about is a time entry report, which I think won't be managed via the invoicing module.
I've attached two docs to show what I mean. To provide a time accounting to my clients, I generate a time entry report for that client, email it to myself, and simply cut and paste it into a word doc to send to them. (I removed some unneeded columns in both examples)
The old one had a summary by project at the top, then the details by date. The newer ones no longer have the summary, which was a very useful feature I'd love to get back. It's true the time is summarized on the invoice, but the two docs sometimes to to different people in the client org.
There is every chance that it is user error on my part - any assistance in getting it back would be much appreciated.