BUFFALO, N.Y. — There have been new developments in the ongoing contract fight between Catholic Health and union workers.

Health system leaders say CWA Local 1133 presented Mercy Hospital of Buffalo with a 10-day strike notice. The strike is set to begin at 6 a.m. on October 1, one day after the contracts of 2,500 health care workers are set to expire. A large majority, 97%, of union representatives voted to authorize a strike earlier this month.

Catholic health administrators say they've created a contingency plan to keep Mercy Hospital open during the strike. They also say Mercy Hospital, Kenmore Mercy Hospital and the Sisters of Charity St. Joseph Campus each filed unfair labor practice charges against the Communications Workers of America.

The union is accusing Catholic Health of refusing to raise wages. In addition, a recent survey shows staffing shortages are threatening patient care.

Catholic Health says it's working to recruit new staff members but the CWA is pushing for staffing ratios that could hurt hospital sustainability.