If the bleeds of rectangular artwork overlap, you can resolve them automatically. You do not need to select the artworks.

• Select Object > Resolve Rectangular Bleeds.
  Tip: If you set the Nudge distance in Preferences under Measurements to the same size as your Bleed margins preference, you can use the Bleed tool to select a bleed line, and use the arrow keys to set the bleeds.

The automatic bleed resolution feature only works for rectangular bleeds.