How many frames (12 fps) for an intro/title?

Is 48 frames good or is it too long? I’ve handwritten 12 frames for the title and copy pasted it 4x to stretch it to 48. If I cut it to 36, would it be too short then? I plan on adding a “credits section” since it’s a fan animation for three creators and an “Animated by (my name)”. The intro ends at 96 frames since it’s also a song animation (Valentine by Laufey). What would be the best decision when you can’t put an outro because the song ends by the end of a lyric? Should I insert the chorus and then add the credits in the end or stick with the credits in the intro? Thanks!