Problem you have encountered:

After 30 days with no errors the errors page in a project stops showing any information and simply redirects to the getting started guide.

What you expected to happen:

The error page with search and access to historic errors is shown

Steps to reproduce:

create a project. Trigger an error wait 30 days and load the page.

Other information (workarounds you have tried, documentation consulted, etc):

It is possible to work around by triggering a error log into the environment

gcloud --project=${project} logging write --severity CRITICAL --payload-type=json test-errors-log \
  '{"serviceContext":
    {"service": "manual-testing"},
    "message": "Test Error\n at /test.js:42:42",
    "context": {"httpRequest":
      {"url": "/test","method": "GET","responseStatusCode": 500}}}'