Check existence of file when sheduling a download, not when the download starts

The existence of a file is checked when a download starts, i like to be asked what to do then, as i often wanna overwrite the existing file (e.g. same video but different resolution), while other times i'm just not aware that i already have it.
So if FDM would check for the existence of the file when i add the download, i don't have to be at my computer to click the correct button, when the download starts (maybe an hour later).