ethereum names execution layer upgrades by @efdevconnect cities. 2 upgrades/yr catches us up in 2030! '25 H1/H2 : Prague/Osaka '26 H1/H2 : Amsterdam/Bogota '27 H1/H2 : Istanbul/Bangkok '28 H1/H2 : Buenos Aires/'26 city '29 H1/H2 : '27 city/'28 city '30 H1/H2 : '29 city/'30 event