Differentiating Pre-paid reservations from Hotel Collect

In the last few months we have noticed some reservations coming in as pre-paid to booking.com.  Our set up has always been hotel collect, so the pre-paid reservations are causing some confusion.  To streamline things we would normally have pre-paid and hotel collect reservations come to our PMS on different rate or tariff codes so that we can easily assign proper charge routing.  However, I don't see a way to do that in the booking.com extranet.

We use V1 and iHotelier.  Anyone else have these problems?  How did you handle?