Considering that the 1987 supernova was so far away, it is quite possible that the neutrino wave they detected then was simply the -last- wave before the visible light arrived. No one has on site measurements, so no one can say if there was or wasn't multiple neutrino shockwaves. The big wave could have gotten here 20 years before then and the technology wouldn't have noticed it.....and such a hypothetical wave would have -had- to be FTL.

 

Be interesting to see if this is a measurement error, an unknown effect,  or if Einstein's relativity theory's have loopholes after all.......