I have a data point for the soft landing or otherwise of partner cards. My wife has my Gold partner card and I nominated her on 23 November 2017. Her year runs 8 November to 7 November so her status should be valid until the end of 2019, but with the known IT glitch it has actually expired as of the end of 2018. I am currently fighting a battle with BAEC to get the extra year of status she is entitled to, but because it didn't happen in time I can now confirm that she has NOT received a soft landing to Silver. She received a downgrade letter a few weeks ago saying "You didn't earn enough tier points to retain your Silver status" (my emphasis), and today her status in the app changed to Bronze and a lounge computer tried to refuse her access to the lounge.