The English future perfect tense shows a combination of
future time and the present perfect tense: an action or event
that started in the past, is starting now, or will start in the
future and will be completed at some future time.

Sentences in future perfect tense can be negative as well
as affirmative. The negative form is

will + not + have + the past participle
(third form of the verb)

The combination will + not is often contracted to won't.

Examples:

will not (won't) have finished something

will not (won't) have gone somewhere

will not (won't) have seen someone

will not (won't) have done something

will not (won't) have had something

will not (won't) have taken place

The meaning of the negative forms is partly the same as
the affirmative forms: the action or event started before
now, is starting now, or will start after now; the difference
is that the verb after "have" will not be finished.

Examples:

We're running behind schedule We will not
(won't) have finished the work by the deadline.
(At the deadline the work still won't be finished.)

Bob left work at 5:00 and his house is about
30 miles from his office. He will not (won't)
have arrived home until after 5:30.

Eun-Mi just started graduate school. She will not
(won't) have completed work for her Master's
degree for at least one more year.

We don't have to wait for Julio. He will not (won't)
have finished his test for at least another hour.

We'll have dinner later than usual tonight.
I put the roast into the oven only 30 minutes
ago, so at our normal dinner time it will not
(won't) have finished cooking.

If you call Judy at 6:00 AM, she won't be
in a good mood because she will not (won't)
have had her coffee yet.