As I said, the rule amendments look to be pretty minor as they...

As I said, the rule amendments look to be pretty minor as they relate to this case. Unless otherwise stated in those comparisons (a google search showed quite a few legal sites that explained the amendments), you can take the current published rules as applying to the FAR vs COP case as far as I can see.
I just assumed if one were to make a statement that the current Arbitration rules were the wrong ones for this case, a little research would have been done first. They were, after all, amendments rather than a complete new set of rules.
Also, one of the points emphasised in www.mondaq.com article was:

"While the revised ICC Rules will apply to arbitrations commenced after 1 March 2017 irrespective of the date of conclusion of the arbitration agreement, the new Expedited Procedure Rules will only apply to arbitration proceedings based on arbitration agreements concluded after 1 March 2017, i.e., after the Expedited Procedure Rules enter into force (Article 30(3)(a))."

It seems that, unless both parties specifically want the 2012 rules, 2017 rules apply by default anyway (except regarding the Expedited Procedure Rules).