Resolve "Update user guide with 4.2.1 references"

source/install.rst

@@ -106,14 +106,14 @@ Instructions on how to install XIOS can be found on its :xios:`wiki<>`.
 .. hint::
 
    Prior to NEMO version 4.2.0 it was recommended to use XIOS 2.5 release. However, 
-   versions 4.2.0 and beyond utilise some newer features of XIOS and users will need to
-   upgrade to the trunk version of XIOS
+   versions 4.2.0 and beyond utilise some newer features of XIOS2 and users will need to
+   upgrade to the trunk version of XIOS2. Note 4.2.1 does not support the use of XIOS3.
 
    This can be checked out with:
 
    .. code:: console
 
-       svn co http://forge.ipsl.jussieu.fr/ioserver/svn/XIOS/trunk
+       svn co http://forge.ipsl.jussieu.fr/ioserver/svn/XIOS2/trunk
 
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 Download and install the NEMO code
@@ -130,7 +130,7 @@ modifications, can clone the repository at the release tag:
 
 .. code:: console
 
-    git clone --branch 4.2.0 https://forge.nemo-ocean.eu/nemo/nemo.git nemo_4.2.0
+    git clone --branch 4.2.1 https://forge.nemo-ocean.eu/nemo/nemo.git nemo_4.2.1
    
 Experienced developers who may wish to experiment with other branches or code more recent than the 
 release -perhaps with a view to returning developements to the system, can clone the main repository 
@@ -140,7 +140,7 @@ and then switch to the tagged release:
 
     git clone https://forge.nemo-ocean.eu/nemo/nemo.git
     cd nemo
-    git switch --detach 4.2.0
+    git switch --detach 4.2.1
 
 
 Description of 1\ :sup:`st` level tree structure
@@ -187,6 +187,9 @@ the installation directories used for XIOS installation
    %XIOS_HOME    /home/$( whoami )/path/to/xios-trunk
    %OASIS_HOME   /home/$( whoami )/path/to/oasis
 
+.. note::
+   Any reason not to add ``build_arch-auto.sh`` to 4.2.1?
+
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 Preparing an experiment
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