A new sailing record was set recently, which didn't _quite_ beat 40 days - it took them 40 days and almost 11 hours.
If you've ever seen a SailGP boat flying up out of the water on their hydrofoils and doing 100kmh - imagine a 32m long 26m wide ocean going trimaran doing the same thing in a non stop circumnavigation of the globe. I think they _averaged_ 27knots or 50kmh!
If you _haven't_ seen the SailGP boats and are curious, here's somewhere to start: https://youtu.be/BQWOoP-Iwn8
Also FYI the link to "Aves Æternæ" is broken.
Though at high altitudes the winds are such that it would be less of an airship and more of a steerable balloon.
You'll get about 1/15-th of the lithium+water mass as hydrogen. So if you want to replenish 1 m^3 of hydrogen at STP (or around 1/8-th of the gas bag volume), you'll need around 600 grams of reagents.