Core Update Done, GSC Bug Fixed, Mueller On Gurus – SEO Pulse via @sejournal, @MattGSouthern

Welcome to the week’s Pulse: updates affect when you can start analyzing core update performance, how much you can trust your impression data, and what Google’s CEO thinks AI will do to software security.

Here’s what matters for you and your work.

March 2026 Core Update Is Complete

Google’s March 2026 core update finished rolling out on April 8. The Google Search Status Dashboard confirms the completion.

Key facts: The rollout took 12 days, starting March 27 and finishing April 8. That’s within Google’s two-week estimate and faster than the December update, which took 18 days. Google called it “a regular update” and didn’t publish a companion blog post or new guidance. This was the third confirmed update in roughly five weeks, following the February Discover core update and the March spam update.

Why This Matters

You can now run a clean before-and-after comparison in Search Console. Google recommends waiting at least one full week after completion before drawing conclusions, which means mid-April is the earliest window for reliable analysis.

A ranking drop after a core update does not mean your site violated a policy. Core updates reassess content quality across the web. Some pages move up while others move down. Roger Montti, writing for Search Engine Journal, suggested the spam-then-core sequencing may not have been a coincidence, describing it as clearing the table before recalibrating quality signals.

What SEO Professionals Are Saying

Lily Ray, VP, SEO & AI Search at Amsive, noted on X that YouTube has gained visibility since the core update began rolling out:

“Just checked a client that ranked in AI Overviews last week and now the top 4 links in AI Overviews are all YouTube.

Let me guess: the core update was another way for Google to boost YouTube, like it did with the Discover core update.”

Aleyda Solís, SEO consultant and founder of Orainti, is running a poll on LinkedIn asking how the update impacted peoples’ websites. Currently, most respondants say the impact of the update with either positve or not noticeable.

Read our full coverage: Google Confirms March 2026 Core Update Is Complete

Google Fixes Search Console Bug That Inflated Impressions For Nearly A Year

Google confirmed a logging error in Search Console that over-reported impressions starting May 13, 2025. The company updated its Data Anomalies page on April 3 to acknowledge the issue.

Key facts: The bug ran for nearly 11 months before Google publicly acknowledged it. Clicks and other metrics were not affected. Google said the fix will roll out over the next several weeks, and sites may see a decrease in reported impressions during that period.

Why This Matters

If your impression numbers have looked unusually healthy since last May, this bug is likely part of the reason. The correction will change what your Performance report shows, but it will not change how your site actually performed in search. The impressions were logged incorrectly. Your actual visibility may not have changed.

Teams that reported impression-based metrics to clients or stakeholders since May were working with inflated numbers. Click data provides a cleaner signal for performance analysis while the fix rolls out. Treat May 13, 2025 as a data annotation point, similar to how you would mark an algorithm update date in your reporting.

What SEO Professionals Are Saying

Brodie Clark, independent SEO consultant, flagged the issue on March 30, four days before Google’s acknowledgment. He wrote:

“Heads-up: there is something bizarre going on with Google Search Console data right now.

Similar to the changes that came to light after the disabling of &num=100, impressions are again skyrocketing for specific surfaces on desktop.”

Clark documented impression spikes across merchant listings and Google Images filters on multiple ecommerce sites and called for the Search Console team to investigate.

Chris Long, co-founder of Nectiv, wrote on LinkedIn: “Holy moly SEOs. It turns out Google has been accidentally inflating impressions in Search Console reports for ALMOST A YEAR.” Long noted that Google did not indicate how much impressions would decrease, and that the profiles he checked appeared stable so far.

Source: Google Data Anomalies in Search Console

Pichai Says AI Could ‘Break Pretty Much All Software’

Google CEO Sundar Pichai said AI models are “going to break pretty much all software out there” during a podcast conversation with Stripe CEO Patrick Collison. The interview covered AI infrastructure constraints and security risks.

Key facts: Pichai framed software security as a hidden constraint on AI deployment alongside memory supply and energy. When investor Elad Gil mentioned hearing that black market zero-day prices were falling because AI was increasing the supply of discoverable vulnerabilities, Pichai said he was “not at all surprised.”

Why This Matters

The security conversation may feel distant from daily SEO work, but it connects to the infrastructure your sites run on. If AI accelerates the pace at which vulnerabilities are found and exploited, the window between a flaw existing and an attacker using it gets shorter. That puts more pressure on maintaining current patches and auditing dependencies.

Pichai’s comments were conversational, not a formal Google policy statement. But they came from someone who oversees both the company’s AI models and its threat intelligence operation. Google’s threat teams have been warning about software security risks tied to faster vulnerability discovery.

Read our full coverage: Pichai Says AI Could ‘Break Pretty Much All Software’

Mueller Calls Self-Described SEO Gurus ‘Clueless Imposters’

Google’s John Mueller responded to a blog post by SEO professional Preeti Gupta about how the word “guru” is misused in the SEO industry. Mueller shared his view on Bluesky.

Key facts: Mueller wrote:

“To me, when someone self-declares themselves as an SEO guru, it’s an extremely obvious sign that they’re a clueless imposter. SEO is not belief-based, nobody knows everything, and it changes over time. You have to acknowledge that you were wrong at times, learn, and practice more.”

Gupta’s original post explained that in India the word guru carries deep cultural and spiritual meaning that is trivialized when SEO practitioners use it as a self-applied label.

Why This Matters

The core of what Mueller said is that SEO changes over time and that nobody has it all figured out.

Just look at what happened this week. Core updates continue to happen without a clear explanation of what changed. A basic logging bug in Search Console went unnoticed for nearly a year. The tools and signals we rely on every day are imperfect, and treating any methodology or perspective as settled knowledge is how mistakes get made.

Read Roger Montti’s full coverage: Google’s Mueller On SEO Gurus Who Are “Clueless Imposters”

Theme Of The Week: The Day-to-Day Work Continue

The speculation about where search is going has never been louder. But this week’s events were a core update finishing, a data bug getting patched, and a Google Search Advocate reminding people that nobody has all the answers.

The future Pichai describes may be coming, but it hasn’t arrived yet. Right now, the job is still reading your Search Console data, waiting for a core update to settle, and staying honest about what you do and do not know.

Mueller’s comment that SEO “is not belief-based” and “changes over time” is as good a summary of this week as any. Those who will succeed in the next version of search are probably the ones paying attention to this version first.

Top Stories Of The Week:

Here are the main links from this week’s coverage.

More Resources:

For more context, these earlier stories help fill in the background.

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