You're quite correct that there were various routes Leah could have took when she walked to walk. Several of them were mentioned in the TVP's re-appeal for witnesses in August 2020 (mkfm.com 11/08/2020):
Senior investigating officer, Detective Chief Inspector Andy Howard, of the Major Crime Unit, said: “On the morning of Friday, February 15, 2019, Leah left her home address in Quantock Crescent. We know that at 8.07am, she was spotted on a CCTV camera in Leigh Hill, just a matter of metres away from Quantock Crescent.
“At 8.16am, Leah was seen again on CCTV in Buzzacott Lane, approximately a ten minute walk from her home address. She was heading in the direction of Dulverton Drive, towards Tellytubbie Hill. However since that sighting on CCTV, there have been no further confirmed sightings of Leah at all.
“Leah walked to work in Knowlhill most mornings, and it is believed that she was on her way to work as usual at this time. Leah would often take different variations of her walking route; we know that on Wednesday 13 and Thursday 14 February that Leah crossed from Furzton into Shenley Lodge and walked up Faraday Drive towards Knowlhill; but we also know that she would sometimes walk the routes that took her directly around part of Furzton Lake.
“Leah’s workplace is in Davy Avenue, which means that Leah’s walk to work is approximately two miles long. It is a busy route through largely residential areas, and therefore I believe that at such a busy time in the morning it’s highly likely that other members of the public will have walked, cycled, or driven past her. Somebody must have seen Leah after she passed the CCTV camera on Buzzacott Lane.
“I would like to reach out and appeal to the residents and commuters in this area, particularly Buzzacott Lane, Dulverton Drive, Loxbeare Avenue and the roads close to Furzton Lake, as well as Faraday Drive and the roads surrounding it. Were you travelling along the H7 Chaffron Way that morning?
“We know these locations were such a feature of Leah’s weekday routine. She would have been walking along these roads and streets, between Emerson Valley, through Furzton and Shenley Lodge and into Knowlhill habitually between 8am and 9am each weekday morning.
Four facts we definitely know from Friday 15 February 2019 are:
1. CCTV footage of Leah at Leigh Hill at 8.07 am
2. CCTV footage of Leah at Buzzacott Lane at 8.16 am
3. Witness sighting at Teletubbie Hill at 8.20 am
4. Leah's phone leaves the network at 8.34 am on the north side of Furzton Lake, near to the Premier Inn.