Permanent licenses do not expire. Trial licenses have expiration dates, typically 30 days after the installation date.
When trial licenses expire, module license checks fail and the modules stop working. If the Web Portal module fails, you cannot access the product.
Because the License Management UI operates behind the Web Portal module, you must upload your permanent license file or extended trials before the 30-day license for the core features expires. Otherwise, the UI locks and you cannot upload the license file.