In the climax of a piece I'm arranging, I want a Bb trumpet to go up to the C two 8ves above Middle C (concert pitch). This is the highest note in the piece. When I write this in Sibelius, I get a somewhat red notehead indicating that the pitch is at or beyond the limit of what the instrument can play. This is different from the bright red notehead which means that a note simply isn't possible.
I would like to not have to avoid the high C, but not being a trumpet player, I'm not sure whether this would in general be too high. Sibelius can be quite strange with tessaturas sometimes. The question: Is it ok to leave this note in the arrangement? How strictly should I abide by Sibelius's suggestion?