Did they say when this went into effect I was there last week Jan 20th (for Jan 21 AC57) and went to both the B and C F lounges with no issue. I also have an email from Jan 20th from the concierge confirming we have access with no mention of it ending anytime soon let alone within a week.
If this is actually now the case that’s very disappointing but I guess I’m glad my first and last visit was right before the change so at least I got to go once.