Well' fwiw,It's maybe not necessary to add this,but just recently my 4 stroke outboard Yamaha was flooding over just as this instance here. Sometimes flood over,sometimes not. A very experienced engine(I thought I was @ 72!) mechanic told me to always run the carb dry to keep the needle tip away from the seat. Keeping the carb bowl full for weeks on end will 'ring' the rubber tip,resulting in possible not sealing properly,resulting in the intermittent overflow. He said I didn't need a kit,just a needle and bowl gasket. End of story,this fixed the intermittent overflow issue.
Between 1976 till about 2011/13?? all my Wheel Horses (3) Kohlers and my (2) Snapper self propels with Briggs sat all winter long with fuel in their carbs. Within a year or two after Ethanol going to 10% "all" of their needle/seats had been upgraded to the newer versions that withstand the ethanol fuel.
Since then I run my tractors dry and use Sta-bil too when stored over a month even. I had never changed even one needle/seat in over 3 decades and never ran one dry. I never once experienced fuel in my oil, not one carb issue at all, not even a slow start in over 30 springs, but then the fuel corps added crapolla to all our fuels and so it all began.
I ran Ethanol free pump fuel until it got impossible to locate around here. Buying it off the shelf now would actually cost me more than replacing the entire carbs on them every spring mowing over 2.5 acres. Besides, I've had no issues at all since upgrading all their needle/seats. I still wouldn't let one sit long with fuel in the carb.
The issue I've seen is the old rubber needle tips swell/deform with ethanol so they won't slide up/down inside the carb right or fit inside the seat to seal off the fuel as it should. Then the engine just fills up with fuel when it sits. I've personally seen a couple friends with gravity fed mowers (without fuel pumps) with bent/broken connecting rods because the cylinder was so full of fuel. One was a very nice older Deere with only 66hrs on it. The owner simply failed to check the oil level on their first spring startup or they'd noticed it was full of gas. They just hopped on their mower, started their engine and bam, got a very rude awakening!
Then called me wanting to know whats wrong with their mower?
Answer: Sadly, in the end its the mowers owner.