xAI's September 14 announcement that Grok 4.8—a 2.5-trillion-parameter model trained on its new C++ stack—had finished pre-training and entered reinforcement learning set the timeline expectations, yet the model remains unreleased as of November 6 following Grok 4.7's September 21 launch. Musk's October 30 comment acknowledging longer-than-expected timelines has reinforced trader caution around post-training safety, evaluation, and deployment steps typical for frontier large language models. The tight spread between a no-release-by-November-30 outcome and early-to-mid November dates reflects uncertainty over whether the RL phase can conclude quickly enough for an API or platform rollout before month-end, consistent with xAI's recent 4-series cadence but tempered by prior slippage on larger updates.