Inconsistent flightstone/crest upgrade results

Snapshot: dc8ccb07398043d79a7107528fa12a4e

Doing a Flightstone/Crest upgrade search, if I set the maximum upgrade level to 431 or less, my top result is the Underlight Globe at ilevel 398 and is a -0.17% downgrade.
However if I set the maximum upgrade level above that (434 or greater), then it says the Underlight Globe, still at ilevel 398 is a +0.28% upgrade.

Since the end result is ilevel 398 regardless, shouldn’t the upgrade/downgrade % remain the same too?

I can take a look at it… it is theoretically possible for the results to shift slightly, but that should be rare.

For background, it is too slow to do a full best in bags optimization with each item in the list, so we use some heuristics to do a “partial” best in bags for each item in the list. Different settings can produce slightly different starting points, which can result in slightly different rankings.

(Usually it takes a couple of seconds for best in bags to complete… now multiply that by N items in your list… and you can see why we have to get clever with list rankings… we’re going to have to keep an eye on the new upgrade search because the list could get very long, so we may have to come up with some even faster heuristics to keep it from slowing down too much.)