Massive LSR spike from single missed batch — Buy Box gone, any way to recover faster?

I was hospitalized and during that time I missed confirming one large batch of FBM shipments. That single mistake caused a massive Late Shipment Rate spike and Amazon removed my Buy Box across all ASINs. Since then I’ve had zero late shipments and operations are fully fixed, but all listings say “Not Featured Offer eligible.”

Support and Account Health keep telling me it’s metric-based and I just have to wait, which puts me in a catch-22 with no Buy Box and no way to dilute LSR.

For anyone who’s actually been through this: did your Buy Box come back once the 10-day window cleared, or did it take the full 30 days? Is there anything that helped, or is waiting the only option?