Comment (by Samuel Cupp):

You should only sync in one of either LeanBSSN_adm2bssn or LeanBSSN_Boundaries but not both, which would be the behavior with this change. If you want to be consistent with your later scheduling, I think you put the sync on the Boundaries function and not the adm2bssn, but that’s ultimately up to you.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2648/empty-applybcs-call-in-leanbssnmol