wrote

The Honda manual states that the mower should be stored with gas in the
tank.
Containers are all sealed.

They state the tank should have stabilizer and be full to keep out oxygen
also.

Honda also notes fuel can deteriorate in as little as 30 days.

Fuel
Gasoline will oxidize and deteriorate in storage. Old gasoline will
cause hard starting, and it leaves gum deposits that clog the fuel
system. If the gasoline in your mower deteriorates during storage, you
may need to have the carburetor and other fuel system components,
serviced or replaced.
The length of time that gasoline can be left in your fuel tank and
carburetor without causing functional problems will vary with such
factors as gasoline blend, your storage temperatures, and whether
the fuel tank is partially or completely filled. The air in a partially
filled
fuel tank promotes fuel deterioration. Very warm storage
temperatures accelerate fuel deterioration. Fuel deterioration
problems may occur within a few months, or even less if the gasoline
was not fresh when you filled the fuel tank.
The Distributor's Limited Warranty (page 19) does not cover fuel
system damage or engine performance problems resulting from
neglected storage preparation.
You can extend fuel storage life by adding a gasoline stabilizer that is
formulated for that purpose, or you can avoid fuel deterioration
problems by draining all the fuel from the fuel tank and carburetor.
Adding a Fuel Stabilizer
When adding a fuel stabilizer (page 18), fill the fuel tank with fresh
gasoline. If only partially filled, air in the tank will promote fuel
deterioration during storage. If you keep a container of gasoline for
refueling, be sure that it contains only fresh gasoline.
1. Add fuel stabilizer following the manufacturer's instructions.
2. After adding a fuel stabilizer, run the engine outdoors for
10 minutes to be sure that the treated gasoline has replaced the
untreated gasoline in the carburetor.
3. Turn the engine OFF and turn the fuel valve to the OFF position