future perfect

If they’re following their schedule, they will have arrived yesterday. - Jeżeli przestrzegają rozkładu, to już wczoraj przyjechali.

Czy dobrze rozumiem te zdanie?

PS Czy można też powiedzieć: "If they're following their schedule they must have arrived yesterday."
" If they're following their schedule, they arrived yesterday."

o tym zagadnieniu bylo niedawno na forum:

https://www.ang.pl/forum/grammar-is-fun/252053

If they’re following their schedule, they 'will' WOULD have arrived yesterday.
If they're following their schedule they must have arrived yesterday." ok
If they're following their schedule, they arrived yesterday. ok

Te pierwsze zdanie wzięłam ze strony BBC i było napisane z "will".

ale, niestety to jest zle.

Czyli wszędzie jest źle? Bo ja się spotykam z taką konstrukcją dosyć często.

to jest poprawne.

If they’re following their schedule, they will have arrived yesterday = If they’re following their schedule, they must have arrived yesterday. yesterday.

Both of them convey a conclusion drawn about a past circumstance.

The same sense of will shows when a deduction is voiced about a present circumstance:

His name is Helmut Schmidt, you say? He will be German then.

His name was Helmut Schmidt, you say? He will have been German then.

ok, ale mogę też powiedzieć : His name was Helmut Schmidt, you say? He must have been German then...to akurat do przeszłości się odnosi .

wg mnie (ale co ja moge wiedziec) trzeba pamietac ze 'yesterday' to jest przeszlosc.

Helmut Schmidt died in the siege of Fort George in 1812.
He will have been German.

He WAS German ;) past simple and " will' sentence soon afterwards ,hmmmm ..perhraps i'm lacking of knowledge my dear :)

He will have been German, but you are dumb.
Get lost, pipsqueak.

Well well well ,I am not blind is for all I can tell you - you are NOT sitting in the centre of this world so I'm better off reading this ! Don't you ever tell me' get lost you' or i'll tell you how angry I can be -I hate abusive language u twat I won't let anyone disrespect me , right? I guess you;ve just missed your daily wank - then bring your back up to someone else not me. If your fiancee had left you all alone it is not my fault .First you'd have to have known me and then you can tell something about me , otherwise just pipe down and get your language straight and forward ,go to pubs and please someone else and find happiness - loneliness is killing :(My advise - get back to yourself and take off your glasses and see world as it is Rob@ greetz :) )

>>> but you are dumb. Get lost, pipsqueak
ANYONE who resorts to personal attacks has ALREADY lost the argument. We do not permit such personal attacks on this forum and your posts will be banned unless you moderate your language and stick to arguments about language issues.

I guess it is just all about somebody's character and personality - I'm not that kind of guy to fall out over irrevelants but no one should have said so to push others around. . Let's better stick to the issues instead of that:) I am not considering myself as better than the rest but thank Goodness, I do not have complexes .