Why the diversity index remains in place?

This Chron article discusses the Supreme Court litigation that is allegedly behind the decision to delay overhauling SFUSD's diversity index rules:
Administration backs white school parents in integration appeal

The court cases in Seattle and Louisville question the use of race as a criteria for school enrollment. Clearly the results of these cases could impact SFUSD's enrollment policies. But I think there are other more pressing reasons—like the lack of clear consensus of political will of the sitting BOE—that explain the delays.