I think the bug is not a bug, but simply how it's made. Spectral arrows are their own special arrow type (they're not tipped arrows), so you can't change the duration, nor can you change the effect (without commands).
And SLScool, is a bug report really the best place to ask that question?
How does that happen?!
His second bug (first was due to him not noticing bobbing was off in visual settings), which is about elytra not updating until F5, has been open for 110 days now, and this one was solved in 5 minutes. THIS IS ABOUT 31.6 THOUSAND TIMES FASTER!
I've encountered this problem in the first pre-release for 1.10.
If you only had this happen once, please try to make it happen again. Otherwise, this may be invalid.