Slow delivery on October 30th is almost certainly a platform issue affecting multiple advertisers. When you see normal CPMs but 40-60% reduced impression volume despite full budgets, that's Meta's auction system throttling delivery on their end. This isn't your account, creative fatigue, or targeting - it's infrastructure. The pattern today matches previous delivery slowdowns that happen during major traffic transition periods. Halloween eve combines with Meta's backend prep for Black Friday (they typically start system adjustments around November 1st). Your campaigns aren't broken, the platform is temporarily constrained. Meta's status page won't acknowledge this because they only report complete outages, not delivery throttling. Critical action to take (or rather, NOT take): Do absolutely nothing to your campaigns for the next 24 hours. Don't increase budgets, duplicate ad sets, or change bid strategies. When delivery is platform-throttled, any changes you make now will reset learning phase and cause worse performance tomorrow when systems normalize. Your campaigns will catch up on impressions tonight or by tomorrow morning as Meta's auction rebalances. If you're running time-sensitive promotions for today specifically, temporarily shift budget to Google Ads or other platforms for immediate reach, but leave your Meta campaigns running as-is. Tomorrow you'll likely see delivery spike to compensate, and any changes you made today will have sabotaged that recovery.