I know @ckrusen’s post is a little older (and that we are still pretty much on Crystal) but in a move towards SSRS we almost lost a complicated RDL because duplicating a BAQ Report simply goes right ahead and overwrites the RDL (because it keeps the same name in the copy).
I found the above article, but not a feature request to have the DEVs simply put in a little popup “Are you sure you want overwrite your RDL?” So here is my request…
We just implemented an upgrade to 10.2.300 and have started using the recommended CustomReports SSRS directory to prevent overwrites during this type of process or a service pack install.