Gannon was reported missing on Monday afternoon, 28th January and had been in school the week before.
Whenever a child goes missing on a Monday, my first thought is always "Who, outside of the individual reporting them missing last saw the child alive and when"?
My brain is theorizing that, IMO, a possible scenario may be that Gannon was actually last sighted on Saturday 26th January shortly after the time the neighbours footage shows her returning home without Gannon. That footage is the last confirmation of Gannon alive prior to his remains being found.
Early on, the neighbour stated that they had checked his footage, but that he was later going through it trying to see if he could find anything to help further the investigation. Is it possible that his footage of Gannon leaving in the truck is actually from Saturday morning? I've seen where LE states that it's Gannon and the neighbour too, but no flat-out statement that the footage was actually recorded on Monday. Perhaps that's just an assumption by all of us. Dad watches the footage too and knows she has lied to him. LE then announce that this is no longer an assumed run away case and foul play is suspected.
If filmed on Saturday, that leaves her until Monday afternoon to get to Florida, using her truck the whole way or a rental as the case may be, dispose of his remains and then return to Colorado to report him missing. The video of Gannon on the floor could have been taken Friday night or Saturday too - disable the geotagging and timing features for media on her phone perhaps? That's possible to do.
Tampering with evidence? Sending texts from his phone saying he was sick etc, to explain away his absence from school the Monday morning. The video footage of her returning to the house was announced as being from Monday afternoon, so we know that's when she came home without him. I've just never seen it explicitly stated that the footage of them leaving was actually filmed Monday morning. I'll have to re-watch it several times to see if she's in the sames clothes as when she left the house. Maybe whatever was bouncing around in the backend of the truck when they left was a small duffle bag with a change of clothes etc - or a bag she put he body into after killing him.
I think Saturday morning to Monday afternoon would allow her to make the trip to Florida, then return to Colorado to report him missing. With a couple hours gap back in the house without him before she actually filed the report ... perhaps to shower and freshen up given the long haul she's perhaps just made.
Upon hubby's return she gets a rental from the airport, knowing it's probably GPS tracked, and puts on 900 or more miles, driving with purpose all over the place to send searchers on their goose chase knowing full well he's already been deposited in Florida. Giving them lots of places to investigate and search while the actual evidence deteriorates in Florida. She knows LE eyes would have been all over her with tails etc. I just can't wrap my mind around a possibility that those eyes were not surveilling her and watching her every move to make it possible for her to move him after he was reported missing. It also makes it possible for the story of "he ran away, was picked up by someone then murdered and dumped by them far away from home" possible if/when his remains were ever identified in Florida" knowing that she was under surveillance and couldn't have taken him there after reporting him missing.
I don't know why, in my head, IMO, I think Gannon was in Florida before he was even reported missing. Premeditation and tampering at it's finest.
Just my .02 cents worth; your mileage may vary.