The Milton Keynes-based outfit finished with both Drivers' and Constructors' championships last season as Max Verstappen eased to glory, with teammate Sergio Perez completing a one-two in the standings.
Aston Martin began the campaign as Red Bull's biggest competitor as Fernando Alonso picked up six podiums in the opening eight races before its challenge fizzled out - rivals able to out-develop their machinery mid-term.
But the Silverstone-based team's end to the year showed glimmers of hope that a renewed challenge could be launched and, with the gap closing between the front and back of the field, Fallows is adamant Red Bull can be caught.
"Inevitably, when you have a team that's doing as well as Red Bull has done since 2022, there will be some kind of convergence on their solutions," Fallows told media, including RacingNews365.
"With the regulations that we have now, it is not particularly easy to have cars that are visually very different.
"What is more interesting is the convergence in lap times that we've seen - people are getting very close and I think that suggests people are probably less able to take a big conceptual step away from the kind of things that we are seeing on the majority of the cars.
"But that doesn't detract from the interest of it.
"We are really into finding lap times from things that are smaller details, we've gotten more detailed elements of the floor and other parts of the car, but there's still a lot of lap time to come.
"We take the approach that Red Bull is absolutely beatable. That's what we are chasing after, we are focusing on them and that's what we are aiming for."
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Red Bull the 'benchmark'
Red Bull was only denied one race victory last season as Carlos Sainz picked up a win for Ferrari at the Singapore Grand Prix, whilst McLaren's Oscar Piastri was the only driver other than Verstappen and Perez to win a Sprint.
Asked whether Red Bull was the focus for victory in just individual events or across a full season, Fallows replied: "Obviously they are the benchmark in terms of performance but really, for us, whoever has the fastest car is the focus.
"Rather than thinking about individual races, from an engineering point of view we have to make a car that's capable of operating at any circuit and being competitive and that's really what we're focused on - making a car that's usable, that's good for the drivers.
"Those sort of competitive stats and how we get close to Red Bull will come after that. If we put performance on the car, then we give ourselves the ability to compete at that level, which is exactly what we want."