All questions
Blue-board meeting

An upstream commercial vessel displays the prescribed light-blue board and bright white scintillating light to an approaching downstream vessel. What arrangement is it indicating?

Short answer

Pass on the upstream vessel's starboard side and repeat the prescribed indication

Article 6.04 uses this upstream-vessel display when leaving passage on its starboard side. The downstream vessel repeats the visual and prescribed sound indication when accepting, producing a starboard-to-starboard meeting. The signal is not general overtaking permission and the article has an explicit small-craft boundary. Revisit The Blue-Board Meeting Procedure.

Quick check

An upstream commercial vessel displays the prescribed light-blue board and bright white scintillating light to an approaching downstream vessel. What arrangement is it indicating?