Kusama Fellowship Referenda 97 is a proposal to increase the parachain validator set size from 600 to 700, keeping the maximum backing group size at 5. This change will increase the total number of usable cores to 140. The proposal also updates the setNDelayTranches from 257 to 299 to maintain the number of assignments per candidate at around 2.33. The justification for this parameter can be found in the ELVES paper and a discussion on the Polkadot SDK GitHub page.