New-Chitose arrival: point of no return?

Hi, I'm going to be arriving at New-Chitose at 8:20am on a domestic flight from Haneda. A wifi device will be waiting for me at the 2F post office, but that doesn't open until 9am. I know it's not long to wait, but I was thinking about first getting my luggage from baggage claim and maybe even getting my JR Pass from the airport JR station while I'm waiting. If I do these things, would I still be able to get back to the 2F post office, or would I be starting my trip off with a disaster?

Thanks!

I just had a look at the map on the airport website. Both you baggage collection zone and the shops on the 2F are in non security areas. So no issues walking between the two.