To express past expectation and assumption, the same auxiliariesA helping verb used with main verbs to express mood, voice and tense. E.g.: I can't stand when I am disturbed. ("can", "am") are used in the case of present expectations and assumptions. However, the infinitives that follow are perfectThe aspect expressing completion. E.g.: He’s finished university. infinitives.

To express prediction, expectation and assumption, the following auxiliariesA helping verb used with main verbs to express mood, voice and tense. E.g.: I can't stand when I am disturbed. ("can", "am") are used.

The following sentences are not in future perfectThe aspect expressing completion. E.g.: He’s finished university., although they contain the same form. They express assumption about a past eventA general term expressing that somebody or something does something or that something happens. E.g.: An apple fell on Isaac’s head..

You won't have heard the news that she's been accepted. (= I don't suppose you have heard the news.)
Ingrid joined our team last summer so many of you will have met her already.