Net_version returning testnet network id rather than mainnet

System information

Geth version: op-geth-1.101308.2 CL client & version: Prysm (v5.0.1) / Teku (24.3.0) OS & Version: Linux (Rocky 9)

Expected behaviour

Attempting to migrate our L1 node from one box to another, repointing Optimism. Both L1's are fully synced.

Previous node: Erigon + Teku New node: Erigon + Prysm

As part of the upgrade I changed the

Following the migration, my net_version RPC calls return 420 rather than 10. Despite the logs indicating we are initialising network=10 as per below. Both L1s are on mainnet.

Backtrace

 Initialising Ethereum protocol           network=10         dbversion=8

curl localhost:8645   -X POST   -H "Content-Type: application/json"   --data '{"jsonrpc":"2.0","method":"net_version","params":[],"id":67}'
{"jsonrpc":"2.0","id":67,"result":"420"}

Commands being run:

./op-node --l1=http://15.235.114.217:8545 --l2=http://0.0.0.0:8551 --l1.beacon=http://15.235.114.217:3500 --network=mainnet --rpc.addr=0.0.0.0 --rpc.port=9545 --l2.jwt-secret=/optimism/jwt.hex --l1.trustrpc --network=op-mainnet --rollup.load-protocol-versions=true --rollup.halt=none --l1.rpckind=erigon

./geth --datadir /optimism/geth --http --http.corsdomain=* --http.vhosts=* --http.addr=0.0.0.0 --http.port=8645 --http.api=web3,debug,eth,txpool,net,engine --ws --ws.addr=0.0.0.0 --ws.port=8646 --ws.origins=* --ws.api=debug,eth,txpool,net,engine,web3 --syncmode=full --gcmode=full --nodiscover --maxpeers=0 --networkid=420 --authrpc.vhosts=* --authrpc.addr=0.0.0.0 --authrpc.port=8551 --authrpc.jwtsecret=/optimism/jwt.hex --rollup.sequencerhttp=https://mainnet-sequencer.optimism.io/ --rollup.disabletxpoolgossip=true --rollup.halt=major --op-network=op-mainnet

ethereum-optimism / op-geth