Constant MAX_SCW_SIGNATURES_PER_REQUEST 

pub const MAX_SCW_SIGNATURES_PER_REQUEST: usize = _; // 200usize

The most ERC-6492 signatures one verify request carries: two for each action of the largest identity update, so no update needs more. The backend refuses a larger max_scw_signatures, and a client sizes its requests by the smaller of this and the published value.