My philosophy is this: if the Intelligence Commissioner needs to approve the initial application, which is valid for one year, I don't see why he shouldn't be involved a year later when an application for renewal of the validity period is made.
Why is an application for renewal made a year later? It must be presumed that new facts have arisen, since a renewal is wanted. At that point, the agency in question will have to submit a written request to the minister, who will have to determine whether the reasons given by the agency are sufficient to authorize the one-year extension.
I don't understand the reasoning for the commissioner's involvement initially, but not for the renewal. I'll make an analogy. It's like appearing before a judge to request a search warrant. It's fine, but a year later, if you want to get an extension of the term, you have to go back to the judge and make a request. It's a bit like that.