The router has supplied internet for years without complaint. That says something about reliability, but little about whether newly discovered vulnerabilities still receive fixes.
Identify the exact device
Find the model and hardware revision on the device or its management interface. Manufacturers may support similar-looking revisions differently. Note the installed firmware version and compare it with the manufacturer’s support page for that exact device.
A message saying “up to date” can mean only that there is no newer firmware offered. It does not establish a promise of future maintenance.
Look for an explicit support statement
Check the vendor’s lifecycle or end-of-support information. Recent NCSC guidance highlights the risk of unsupported internet-facing devices. If the published policy is unclear, ask the manufacturer or the provider that supplied the router rather than inferring support from continued sales elsewhere.
For a provider-managed device, find out who supplies and installs updates before trying a manual firmware change.
Plan the replacement around the job
If security maintenance has ended, plan a move to supported equipment. Record the connection details you are entitled to manage and the features you actually need, such as telephony or a particular mesh arrangement. Follow the provider’s requirements so a replacement does not unexpectedly remove those services.
A regular lifecycle check is more useful than waiting for a visible failure. Put the model, support source and next review date in a short household equipment note.