GitHub Copilot switched to per-token usage billing in June 2026, developers burning monthly quotas in hours with no in-session hard-stop CLI tool

On June 1 2026 GitHub Copilot retired flat subscriptions and moved all plans to AI Credits billed per input, output, and cached token. Developers on Pro ($10/mo) and Pro+ ($39/mo) reported burning 50-plus percent of their monthly quota in a single 2-hour agentic session with no real-time burn signal. One developer burned $6 on a single function-change request. The official GitHub community discussion received 534 comments and 958 thumbs-down reactions out of 1124 total. GitHub's built-in spend cap only blocks overage above the subscription ceiling after quota is exhausted -- it does not warn or throttle within a session. No existing CLI tool reads the Copilot usage events stream in real time, computes credit burn rate per task, and pauses or warns the session when a user-set per-session ceiling is hit. The only community-built tool (copilot-cli-cost, 3 HN points) parses log files after the fact. The gap is pre-emptive per-session guardrail enforcement during agentic runs.