G’day Howler
J.R.Road is an out-and-back: you come back the same way you went out so you can make the walk as long (or as short) as you like. At the bottom of the road at the T-Junction if you turn left it’s a 2km walk to the creek.
Alternatively, you can turn right, and follow England Creek Road as far as you can, then loop back to Mount Glorious via Lawton Rd. That would make it a 25km loop.
It depends on how energetic you feel 🙂
Have fun!
Neil