Been traveling a lot for work. So, we took the Fuel EXe 9.7 (Shimano drivetrain) back to the Trek dealer to have the Sram drive train swapped from her Rail 9.8. They left a message saying they could swap the AXS shifter and derailleur, but the cassette wasn't compatible with the chainring on the EXe and Trek wouldn't have a solution until mid-winter. The EXe 9.9 models have all Sram drivetrains. So, are the chainrings drivetrain specific? I haven't looked at the specs yet. On the Rail, the chainring works with both. If it's possible they are different for drivetrains, maybe the "solution" means they will have chainrings to sell in the Fall. I haven't talked to the LBS yet, but thoughts?