Dought & clear, - - - - Sifat al-Salaah (description of the prayer) - Ruling on member of thecongregation leaving straight after the imam says the salaam.

When the congregational prayer ends and the salaam has been said at
the end of the prayer, when can the member of the congregation move?
Can he move before the imam turns around, or must he wait and not move
before him?.
Praise be to Allaah.
Once the imam has said the salaam, it is permissible for the person
who prayed behind him to move, whether the imam has turned to face the
congregation or has stayed where he is, or he has got up from his
place. But it is better for the person who prayed behind him to stay
put until the imam turns to face the congregation, because of the
possibility that the imam may be sitting so that he can do the two
prostrations of forgetfulness (sujood al-sahw) after saying the
tasleem at the end of the prayer. Even better than this is to get up
only after the imam has got up.
There is an indication that it is permissible to leave as soon as the
salaam has been said in the report narrated by al-Bukhaari (875) from
Umm Salamah (may Allaah be pleased with her) who said: When the
Messenger of Allaah(peace and blessings of Allaah be upon him) said
the salaam, the women got up when he finished his tasleem and he
stayed in his place for a while before getting up. One of the
narrators of the hadeeth said: We think, and Allaah knows best, that
this was so that the women could disperse before any of the men caught
up with them.
With regard to the report narrated by Muslim (426) from Anas (may
Allaah be pleased with him) who said: The Messenger of Allaah(peace
and blessings of Allaah be upon him) led us in prayer one day, and
when he had finished praying he turned to face us and said: "O people,
I am your imam, so do not go ahead of me in bowing, prostrating,
standing or finishing, for I can see you from in front of me and
behind me," what is meant by "finishing" here is the salaam.
Al-Nawawi (may Allaah have mercy on him) said: The words of the
Prophet(peace and blessings of Allaah be upon him): "so do not go
ahead of me in bowing, prostrating, standing or finishing" indicate
that it is haraam to do these things and others that are similar to
them. What is meant by finishing is the salaam. End quote.
Imam al-Shaafa'i (may Allaah have mercy on him) said inal-Umm(1/151):
The one who has prayed behind an imam may leave when the imam has
finished the salaam, before the imam gets up, and he may delay that
and leave after the imam leaves, or leave with him, which I like
better. End quote.
Ibn Qudaamah (may Allaah have mercy on him) said inal-Mughni(1/328):
It is mustahabb for the one who has prayed behind an imam not to get
up and leave before the imam, in case he remembers something that he
forgot and does the prostration of forgetfulness. End quote.
And Allaah knows best.