But is E5 still available? Come September E10 will replace E5 as far as I am aware.
Unless anyone is running an old vehicle, then don't worry about it.
The E5 "protection grade" will be available for the forseeable future, albeit probably marketed as a "super" and costing more. Use that if you are concerned.
This is a good sensible summary of the situation.
https://www.fbhvc.co.uk/fuelsThe politics of such issues is always questionable, but don't lose sleep. There are far more important things to worry about.
If you are concerned about fuel consumption, walk more and drive more slowly. You won't notice 1% change in fuel economy or power. "Modern" cars will be fine, certainly anything* made this century.
* - someone will probably give an example of a car which isn't suitable.