Start Gen4 from the newly promoted Gen3 rolling champion (team-preserve). Train the 8 Champion Forge challengers with the next run-number-derived seeds, use the strengthened multi-seed promotion gate, and update sideswipe-pretrain-latest only if a challenger beats the Gen3 champion without regressing either 1v1 or 2v2.
Start Gen4 from the newly promoted Gen3 rolling champion (team-preserve). Train the 8 Champion Forge challengers with the next run-number-derived seeds, use the strengthened multi-seed promotion gate, and update sideswipe-pretrain-latest only if a challenger beats the Gen3 champion without regressing either 1v1 or 2v2.