"All that we know is that around 8:40 pm Amanda Knox was still at Raffaele's apartment. Jovana Popovic, a Polish student who knew Raffaele, came by his apartment to inform him that she no longer required him to give her a drive to the bus station. Jovana did not see Raffaele, and she was told he was in the bathroom by Amanda.[3] Sollecito received a phone call at 8:42 pm that was handled by the cell tower covering his apartment so he was likely at the apartment until at least 8:42 pm.[4]"
Ok, Jovana's time...it can't be that specific as to the minute. She could gotten there perhaps 5 or 10 minutes earlier or something.
His cell tower...but they could have been walking towards the cottage at that time, but still within his cell tower range.
They turn the phones off walking towards the cottage, because they have already planned this "prank."
It is only a few minute walk to the cottage.
Thanks.