Apple's Ambitious Siri AI Overhaul Hits Fresh Roadblocks, Core Features Delayed to iOS 26.5 and iOS 27

Apple’s long-anticipated and fundamental revamp of its digital assistant, Siri, has encountered significant development difficulties, forcing the company to postpone the rollout of several key features. Originally slated for the March release of iOS 26.4, major advancements are now being staggered across later updates this year, namely iOS 26.5 and the flagship iOS 27 update. The setbacks stem from critical reliability and performance issues uncovered during internal testing, highlighting the immense engineering challenge of integrating next-generation AI into a privacy-focused platform.

The Long-Awaited Promise of 'Apple Intelligence'

For years, Siri has lagged behind rival AI assistants, a vulnerability Apple aimed to resolve with its highly-touted “Apple Intelligence” initiative. The new Siri, sometimes referred to as “Siri 2.0,” was designed to transcend its current function as a rigid command-and-response tool, transforming into a true conversational agent powered by Large Language Models (LLMs).

Among the most anticipated capabilities were features intended to make the assistant more context-aware and personalized. This includes the ability to hold continuous conversations, maintain chat memory, and access personal on-device data—like finding a specific photo or locating a message shared weeks ago—to answer questions. Furthermore, the overhaul promised Advanced App Intents, enabling Siri to execute complex, multi-step actions across various third-party applications with far greater precision than before.

Internally, the new architecture, reportedly codenamed Linwood, incorporates Apple Foundation Models and strategically utilizes Google's custom Gemini model for complex tasks, marking a significant strategic partnership for the company.

Reliability Sticking Points Force a Rethink

The decision to delay the launch, first expected in iOS 26.4, was reportedly made after internal testing revealed a host of stability and performance problems. Engineers discovered that the LLM-powered assistant frequently struggled to process user queries reliably, leading to accuracy inconsistencies and unacceptably long response times.

Crucially, testers identified specific functional issues, including a persistent bug that would abruptly cut users off mid-sentence if they spoke too quickly. Another major roadblock has been the system’s occasional tendency to fall back to the existing OpenAI-powered ChatGPT integration, even when the query was one that the new Gemini-backed Siri should have been capable of handling natively. These issues collectively led to the conclusion that the software was not yet meeting Apple’s stringent stability standards.

This complexity underscores Apple’s unique burden: delivering advanced AI while simultaneously adhering to a local-first and privacy-preserving architecture. While this commitment to user data protection is a key differentiator against rivals, it adds immense engineering overhead compared to cloud-only solutions.

The New, Staggered Rollout Timeline

Rather than launching a single, comprehensive upgrade, Apple is now planning a phased deployment throughout the remainder of the year.

This iterative approach reflects an acknowledgment of the technical hurdles involved in re-architecting a core system component like Siri. By shifting the bulk of the LLM-driven features to iOS 27, Apple provides its teams with a comfortable timeline leading up to the annual flagship iPhone launch.

Practical Takeaways: What This Means for Users

While the delay is frustrating, it reflects Apple's historical prioritization of stability over an aggressive release schedule, particularly for new and unproven technology like generative AI.

For End-Users:

• Maintain Patience: Do not expect a revolutionary 'Siri 2.0' in your March update. The conversational AI you're anticipating will be arriving in May at the earliest, with the full-featured chatbot still months away. The AI experience in the short term will remain largely the same.
• Look for the 'Preview': If you’re testing iOS 26.5, look for a “preview” or beta toggle for new Siri features, which will be the first indication of the coming changes.
• Long-Term View: The delays are fundamentally an effort to ensure the final product is reliable and private. Apple executives have maintained a firm stance that the new AI must not expose user data, a distinction that could ultimately be a long-term advantage despite the shorter-term setbacks.

For Developers:

• Focus on iOS 26.5/27 App Intents: For apps planning to leverage Siri's new cross-app capabilities via Advanced App Intents, expect a longer window for development and testing. Concentrate your efforts on the iOS 26.5 beta cycle for initial integrations.
• Prioritize Stability: Apple’s emphasis on reliability is a clear signal to developers that performance and accuracy in AI integration will be paramount for acceptance into the App Store ecosystem.