Comment (by Roland Haas):

I dug up the old meeting minutes from when LORENE2 was first introduced (from 2016):

http://lists.einsteintoolkit.org/pipermail/users/2016-October/005020.html

basically we introduced LORENE2 to indicate the breaking change and left LORENE as the default version in the thornlist.

At the very least we should be able to update LORENE2 to the current version (assuming no more breaking changes in between) and, if we want to deprecate LORENE1 and remove, possibly only in the release after the next one, switch defaults. The issue is that one cannot compile both thorns at the same time so switching from LORENE1 to LORENE2 will break existing parfiles (for example the gallery example).

Making LORENE2 the default was a decision reached in the ET call on 2018-03-12:

http://lists.einsteintoolkit.org/pipermail/users/2018-March/006122.html

where it says:

--8<--
updating LORENE:

• make LORENE2 the default after verifying that everything compiles and
  that gallery example works with LORENE2
• check that BBH ID from Meudon group can still be read
• create ticket for this
• get this done within a month
  --8<--

and from future minutes, nothing seems to have happened though in

http://lists.einsteintoolkit.org/pipermail/users/2018-October/006610.html

it says

--8<--

• update ET to LORENE2

  • need to check that files can still be read
  • old ticket stated that there would be an abort for some files written by old an read by new LORENE or vice versa
    --8<--
  --
  Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2206/make-lorene2-the-default-lorene-in-the-et