Yes. The classification is assessed on the duties as they actually are at the time of the extension. If the specialist has drifted into general support work, the connection to the employer's proprietary processes is weaker than it was, and the extension is decided on that weaker position rather than on the original approval.
The extension examines today's job
This is the failure mode that surprises companies most, because there was no decision to point to. A receiving affiliate under pressure allocates work to whoever can do it, and a capable specialist absorbs it. Two years later he is competent, valued and doing something that any experienced integrator could do.
The category asks whether his knowledge is of the employer's own product, service, techniques, management or processes, or represents an advanced level of knowledge of them, and a helpdesk queue does not evidence that. Two practical defences exist. The first is structural: define, in writing, a portion of the assignment that is the proprietary work, and keep evidence that it is being done, such as commits, release notes, design documents and training delivered to local staff.
The second is procedural: review the actual allocation of time annually against the approved description and correct drift while it is small. Where the business genuinely needs a different role, address that honestly rather than at an extension.