I think there is (or was) a way to screw up the splay directions when changing the survey shot direction. I can't reproduce the error but I ended up with some splays not inverted while the survey shot had been inverted and I have not manually edited the directions. I inverted the directions using right mouse click>Direction in Drawings but it seems to work fine now. I also checked that in Data, splays are inverted together with the shot way using "Direction <->" in Replace.
Has anyone noticed the same issue and/or has this been fixed explaining why I can't reproduce the error?