The recommended way for safe simulations is that you will never change the Eclis version used by a given simulation.

On the other hand, when designing a new simulation, you generally can move to a newer Eclis version because it will bring fixes, and also because Eclis devlopers work hard at providing upward compatibility

However, there are a few occurrences of broken upward compatibility, which can imply that the user changes some parts of his usual parameter files when changing Eclis version

• version 6.40
  • discontinued launching a series of CMIP6 specifics post-processing in step assemble_and_QC.sh. For restoring these post-processing, you must set UPOSTPRO=$ECLIS/toolbox/postpros_CMIP6.sh
  • does not provide anymore the binaries which update Arpege and Surfex restarts with a new reference date ; you must set DATRES and DATSFXRES for that, and use the version of binaries from Arpege-Climat >= 6.4.1 (even when using an older Arpege or Surfex) , as e.g. :
    • DATRES=~alias/public/packs/arp604_export.01.IMPI512IFC1601.2cz/bin/datres
    • DATSFXRES=~alias/public/packs/arp604_export.01.IMPI512IFC1601.2cz/bin/datsfxres