It makes perfect sense, you're just not seeing it from the call centre person's point of view.
Which is: don't know how this works, no-one has given them instructions on this specific issue, they literally have no idea how long it will take in practice overall and especially for any one specific file. Therefore, pick the answer that means fewer calls and allows them to kick the can down the road a little bit longer. After all, if they tell you it's the shorter one, then you're going to complain you were told [such and such.]
I'm not saying this to make anyone mad, and I'm not blaming the call centre people; that's the likely situation, and that's their incentive.