Up until a few weeks ago, corporate leaders felt confident about what to expect this fall. Offices would reopen after Labor Day. Business travel would resume more broadly. Long-delayed work gatherings, conventions and off-site meetings would finally take place. The swift, startling resurgence of Covid-19 cases and hospitalizations across the U.S. is causing corporate leaders to rip up playbooks for the next few months. No longer is a September return a target for many companies. Some employers, such as banking giant Wells Fargo WFC -0.18% & Co. and managed-care company Centene Corp. CNC -1.59% , have in recent days shifted return-to-office dates to October. Meanwhile, a range of other prominent…
