Sorry going to be a bit pedantic here but to clarify.
You saw I1 availability on the flight. That refers to inventory in the I "bucket" available for sale, not a fare per se.
Ie Various fare buckets can be available on a flight, but that doesn't mean that there are fares filed that book into those buckets.
This is why I contend that the lack of seeing, for example, Business Sale Fares, which usually do book into I inventory on QF is not a reliable guide to this sort of tging. There can be ample inventory with no fares available in amarket (and let's not get into connecting markets!), just as there can be fares filed in a market, but if there is zero inventory (eg I0) then there will be no sale fares available on that particular flight. Yes, existance of a fare showong that books into certain inventory bucket imples availability exists on an individual flight, but the inverse is not necessarily true.
I just feel we need to be careful when using the terms "fares" and "inventory" imo
/pedantic hat off
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