From where Katrina was on video at around 8 pm it would only be a trip of minutes to get to the Tetterhall Lane address. Police have arrested her husband who was at that address when he last saw her at around 9 pm according to him. I do not know if there were children there at that time. Was his story that Katrina was there to do laundry backed up by a "load" of her laundry that would have had to be there? Would she have laundry to do when a weekend had just passed? Would she wait so late to do laundry if she had to be to work the next morning by 8 or 9 am. From where she was living to the town where she worked is about a 1/2 hour drive. She would probably have to be up by 6:30 or 7 am the next morning.
If Katrina was attacked at the Tetterhall address between 8 and 9 pm, likely possible inside locations to have been tested with Luminol would be a laundry room if there is one, the basement, or the garage.
Because of his statement that Katrina left about 9 pm I think he would have driven away in her car at that time in case any neighbors were able to be witness to the car leaving.
Going on the word of previous posters that it is not likely that a body would have made it over several dams between Machesney Park and Byron I offer the following. The distance from the residence to Byron is a little more than 22 miles with a travel time of about 40 minutes down, and 40 minutes back with some additional time to dispose of Katrina's body and drive to where the car was found (I don't think he would have driven the car back to the house and then away again later).
From where the car was found to the Tetterhall Lane house is just over 3 miles and could be walked in about an hour. There was no bus service in that area. That would place arrival back at the house at about 11:30 pm.
You will notice that in the 3rd attachment there is a bridge not far from where the car was found. If TS dropped the body off that bridge the time element would have changed and he could have been back at Tetterhall Lane between 10:15 and 10:30 if he left around 9.
If Katrina was attacked at the house, there would be a lot of cleaning to be done and whatever was used (mop, sponges, brushes, rags, clothing) would have had to be cleaned or disposed of and if her car was parked outside something to hide her body to transport it to the car would likely have been used and that would have had to have been disposed of. It would have been easier for him to have driven the car into the garage to place Katrina into it after closing the garage door.
Possible evidence: Blood splatter or residue matching Katrina's blood type in the house or garage, any cleaning materials used, his clothing with Katrina's blood found on it, his fingerprints being the last ones on the door handle or steering wheel of her car or on her phone or purse.
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