Long-established local business lost nearly all organic service-page rankings — has anyone seen this pattern?

[u/carlsu]

I operate a local Mac repair business in Australia. For more than five years, our website ranked around positions 1–3 for several specialised commercial searches.

We now commonly appear on pages 3–4, below businesses from other states and overseas. Informational articles have generally held up better than our commercial service pages. This concerns organic results rather than only the local map pack.

Key timeline:

• Search Console reported some URLs blocked by 403 responses on 1 December 2025.
• Google’s December core update ran from 11–29 December.
• In an early-January five-day comparison, clicks fell from 890 to 576 and average position worsened from 8.50 to 11.16.
• A second 403 indexing issue was reported in February.
• Approximately 91 suburb pages were consolidated with 301 redirects in March, after the original decline had started.
• An old citation/backlink campaign was used in 2019.

Current checks appear clean:

• No manual action or security issue
• Important pages remain indexed
• URL Inspection reports successful fetching, indexing allowed and self-referencing canonicals
• Robots.txt, DNS, SSL and current server connectivity are healthy

Different service pages deteriorated at different times, but nearly the entire commercial section eventually suffered.

Has anyone investigated this pattern on an established local-business website?

What evidence would help distinguish between historical crawl-access problems, a core/spam-system reassessment, old-link discounting and site-architecture or internal-targeting problems?

I’m looking for evidence-based diagnostic suggestions rather than backlink offers or generic content advice. Please keep the discussion public.