Z.ai releases GLM-5.1 to all Coding Plan users with 5am–11am PT switch window

• Z.ai says the rollout post makes GLM-5.1 available to all GLM Coding Plan users, widening access beyond the earlier limited release.
• The company also highlighted a follow-up post saying users can "switch over" during a 5 am to 11 am PT window, framing it as a way to "take some of the load off Claude."
• Z.ai's Coding Plan page positions GLM-5.1 for agents and IDE workflows, with API-key access alongside the older GLM-5 model.
• Early practitioner feedback was mixed: in one test report, RepoPrompt's author said GLM-5.1 looked weaker than 5.0 on Repo bench and was less reliable on tool calling, while still calling it "a great coder."

The concrete change is broad availability. Z.ai's launch post says GLM-5.1 is now open to all GLM Coding Plan users, and the linked plan page describes that plan as AI coding for "Agents & IDEs" with API keys included. The image attached to the post shows Z.ai benchmarking GLM-5.1 at 45.3 on a "Coding Evaluation" using Claude Code as the harness, up from 35.4 for GLM-5 but still below Claude Opus 4.6 at 47.9 [img:0|Coding evaluation].

Z.ai's follow-up post added an operational detail: from 5 am to 11 am PT, users can "switch over to the GLM Coding Plan," which it said would "take some of the load off Claude." That reads more like a usage window than a permanent routing change, and the post does not spell out rate limits or billing behavior.

The first practitioner check-in was less bullish than the launch framing. In early testing, RepoPrompt's author wrote that 5.1 "does worse on Repo bench" and "doesn't seem to follow instructions as reliably in terms of tool calling," while still reporting that the model was already usable inside the RepoPrompt agent.