engineers in an attack move refuse to reclaim or stop

[SeraphimLeftNut]

Starting around minute 20 on the top left side expansion you will see multiple clumps of engineers in factory attack moves. One of the clumps refuses to reclaim, I do move it around a little, it takes forever to get into formation, then begins to reclaim, then stops. I am zero on mass, and there are clearly reclaims wrecks available. The attack order is also not cancelled as is the case when the engineers no longer have any available reclaim. Therefore they see it, they just can't have it for some reason. I see shit like this all the time in some games and in others there are no such problems.

Do people have an explanation for why this happens and is this a common issue.

gamelog
http://pastebin.com/d2fz669Y