For instance to say something like "I hope that I will have killed the man by tomorrow evening" you can use the aspect suffix.

{qaSpa' wa'leS ram loD vIHoHta' 'e' vItul}

NOW I hope (a non-contunious and not ended situation) that at the moment called "tommorow evening" (an event in the future) the action of killing is over (hence the -ta') suffix.

Is that understandable? (@mayqel)
Is that correct? (@SuStel)

Let's drop the 'e' vItul so that we don't get into questions of whether I hope by tomorrow evening or I will have killed the man by tomorrow evening. Besides, the second verb in an SAO is prohibited from taking aspect suffixes.

qaS'pa' wa'leS ram loD vIHoHta'
before tomorrow night occurs I will have killed the man

This looks right to me. If the -ta' had been left off I'd read it more as a general declaration of activity: I'll be killing men up to tomorrow night. And the qaSpa' doesn't need a completion aspect because we're not talking about the completion of night occurring.

By the way, your original with 'e' vItul doesn't necessarily mean that the hoping happens now (assuming you mean the tomorrow night part to apply to the killing). Maybe I hoped two weeks ago that I'd have killed the man by tomorrow night.

-- 
SuStel
http://trimboli.name