I've been thinking about this all day, and I'm leaning towards shifting most of my spend to Amex (PRG). We fly to Turkey fairly regularly (family) and I like to save up for J redemptions. United had the advantage here (100k, no fees).
After devaluation the same ticket will cost 140k using United. But with AC, it will cost 105k + $73.90 in taxes/fees (on TK), not bad at all. Or with ANA, it's 85k + $321.40. Either way, MR partners now provide the best value. I don't think AA/OneWorld has any good options here.
My CSP AF is due next month, and I was planning on keeping it before the news, but I may just cancel... I would forgo my annual dividend, and I'd miss having a good travel card with no foreign fees. It's going to be a touch decision, because if I shift most of my spend to Amex PRG and use CSP for merchants that don't take Amex and foreign spend, I'm still not sure it'll justify the $95 AF.