Quoted from Caring Citizen:
LE says they know Whitneys vehicle was at Dodge Park and Larch Mountain (east of Gresham/Troutdale) prior to the next timestamp at the gas station.
Route from Starbucks (or could have been her house equally close by) to Dodge Park and then on to Larch Mountain (both places uncovered evidence that is currently mum)
http://goo.gl/maps/51Hph
Note in the above route that it takes just
21 minutes (10 miles) to get to Dodge Park and then it takes another
41 minutes (19 miles) to get to Larch because you essentially have to go back to central Gresham/Trouydale and go back out another way.
Route from Larch Mountain to Gas Station to McMenamins/TroutdaleTerrace shared field area (where the phone was found) and on to Walmart
http://goo.gl/maps/LHpZN
Notice how once you get back into the central area, points B (gas) to C (phone dump) to D (SUV Walmart) are
all very close together.
SUMMARY TIMELINE
6:45am Left the house (alone or not; willingly or not)
7:00ish to 9:00ish am (SUV and/or Whitney and/or her phone) was east of Gresham/Troutdale at Larch and Dodge according to LE (didnt say how known: is it gps on her SUV; is it ping from her phone; is it visual sighting of her; is it ping from perps phone)
8:00ish to 8:15ish am Starbucks called Clint on his cell phone
Sometime after that Clint called Whitneys parents (from where, no one has said)
9:14am ATM card used at gas station (attendant uses card in the pump/no one goes inside)
Small amt of gas bought (this ensures attendant is quick and doesnt go to other customers)
Pumps work like RedBox (slide card, enter zip code, thats it; atm cards work like credit cards in the pump but are a debit; no pin required but zip code is)
No clear proof the attendant saw Whitney but if he did and she was in the car, she wasnt afraid enough of the driver to bail out of the car in this public place of potential freedom
Her phone ends up a mile away and her car just a couple more past that
Snipped for brevity.
Based on this very good information you put together, it appears that there are only *about* 25 minutes unaccounted for if both park areas were visited prior to the gas station appearance at 9:14 AM.
6:45 AM ---> 21 minutes to Dodge ---> 21 minutes back ---> 41 minutes to Larch ---> 41 minutes back = 8:49 AM