Ethereum's previous testnets, Holesky and Sepolia, faced significant configuration and synchronization issues during their attempts to test the Pectra upgrade

Quotes that support claims

Pectra was initially slated to launch on Ethereum mainnet in late 2024 but has faced repeated delays due to client readiness issues and synchronization bugs in the first two Ethereum testnets, Holesky and Sepolia.

Previous Pectra activations on the Holesky and Sepolia testnets ran into configuration issues, pushing back the official release schedule.