How to Straming replication chatch up from archive

Hi,
we have a doubt interpreting documentation. We have a 9.6
installation master+stand-by in streaming replication.
Master database
is in archive mode and WAL archive destination (NFS) is mounted in both
master and stand-by servers.

The question is regarding this part of
documentation:
(https://www.postgresql.org/docs/9.6/warm-standby.html)

If you use
streaming replication without file-based continuous archiving, the
server might recycle old WAL segments before the standby has received
them.
If this occurs, the standby will need to be reinitialized from a
new base backup. You can avoid this by setting wal_keep_segments to a
value large enough to
ensure that WAL segments are not recycled too
early, or by configuring a replication slot for the standby. IF YOU SET
UP A WAL ARCHIVE THAT'S ACCESSIBLE FROM THE STANDBY,
THESE SOLUTIONS
ARE NOT REQUIRED, SINCE THE STANDBY CAN ALWAYS USE THE ARCHIVE TO CATCH
UP PROVIDED IT RETAINS ENOUGH SEGMENTS.

if the master overwrite the wal
BEFORE they are sent to the standby via replication, does the standby
AUTOMATICALLY start looking in WAL archive destination?
Or this step
have to be made by hand?

regards and thanks in advance
MP