Is is permitted to pipeline a QUIT after a BDAT LAST?
RFC 5321 section 22.214.171.124 is quite clear that QUIT can be issued at
any time. The state of the connection doesn't matter.
So yes, a QUIT can be pipelined after BDAT LAST. It doesn't matter
if the BDAT succeeds or fails.
RFC 3030 (SMTP Service Extensions
for Transmission of Large
and Binary MIME Messages)
does not say whether or not BDAT LAST is a synch point per
RFC 2929 (SMTP Service Extension for Command Pipelining).
That would only matter if there were restrictions on when QUIT can
2920 says (3.1) :-
"The actual transfer of message content is explicitly allowed to be
the first "command" in a group."
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