what is meant by "incoming replace" in rtc pending changes?
One answer
In "incoming replace" means that someone executed a "replace" operation on the target stream.
When you accept that "replace" it will replace the current state of your workspace with that baseline.
If you have one or more outgoing change-sets, it will prompt you to ask whether you want to keep those outgoing change sets in your workspace, or whether you want them to be captured in a baseline (a "backup-before-replace" baseline). So you cannot lose those change sets.
Also, if you have saved but not checked-in local changes, it will prompt you asking what you want done with them (e.g. check them into a change set first).