I would NOT be happy if 100LL is discontinued without a 100UL replacement, as it would render my engine inoperable, as it would for many other aircraft owners.
Breathe. That's the fallacious canard fostered by that those with a political axe to grind wrt the politics of environmental regulation, want you to worry about. 100UL may end up more expensive than 100LL; it may end up the same cost. But they won't shut down commerce (piston-dependent **flight training) over it. Which is where **our moribund (that's you and me) subset of the participant membership belongs to.
See, you gotta look at the macro picture. This ultimately goes back to airlines and
ab initio. As long as the airlines have the labor market supply-side captured (i.e. subrogated,
piston flight training financed by personally indebted, optimism-biased aspirants), your ability to put fuel into your politically irrelevant slow-flying lawnmower will continue to exist. We're mere coattail riders of that seedy-on-its-own-right part 61/141 puppy mill industry, good bad or indifferent. Heck, some of us own literal examples of lawnmowers built for-purpose for that industry in the first place (to include paying for the sins of the regulations imposed on its for-revenue counterparts, but I'll digress on that), as our way to buy into the hobby.
You want to talk about making that spam can of yours an actual lawn ornament? Let the US approve
MPL for the airlines. Then watch physical piston flight training vanish like a fart in the wind. At that point we're hosed by lack of airframe vendor support (OEM, and aftermarket especially, alike), not by lack of fuel like you fear. Both 100 UL OR LL would be Eurozone+ priced by lack of economies of scale nationally at
that point, but that's moot. Good night irene for most of the people on here, except for those of us able/willing to pivot to EAB and scoff the fuel toting issue, or content with flying ultralights (I don't belong to the latter, but do the former).
TEL is a red herring.
