Can her frame take wires? If so, and she wants to stick with 11 speed, then Di2 can be done easily. I have a bike I would love to put Di2 on, but can't run the wires, unfortunately, so I would have to go eTap 12 speed, but all the additional bits I would need, has put me off that path so far. However, my mechanical Ultegra works like a dream, so not something I really need to replace at this point.
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Brian | 2023 Trek Domane SLR 7 AXS | 2023 Trek CheckPoint SL 7 AXS | 2016 Trek Emonda ALR | 2022 Trek FX Sport 5
you should learn to embrace change, and mock it's failings every step of the way.