Codespaces spending-limit alert thresholds and notification recipients

Goal: keep organization Codespaces cost awareness low-noise by relying on spending-limit usage alerts instead of per-codespace start, stop, or idle notifications.

When an organization Codespaces spending limit is reached, GitHub blocks new codespace creation until the limit is raised or the next billing cycle begins. Usage alert emails are the documented low-noise mechanism, but it is unclear whether alert percentages are fixed or configurable, and whether recipients are limited to organization owners and billing managers or can extend to individual users, Slack, or webhooks. Behavior may also differ across GitHub Free, Team, and Enterprise plans, and alert delivery can lag actual usage.

Current thresholds and recipient options must be confirmed in organization billing settings because behavior varies by GitHub plan and alert delivery can lag actual usage.

Are spending-limit alert percentages fixed, or can organization admins configure custom thresholds?

Can alert recipients include individual users, Slack channels, or webhooks, or are they restricted to organization owners and billing managers?

Does available alert configuration vary by GitHub plan?