User samples: 2016 n=3193, 2018 n=6893, 2020 n=6459
Users in >=2 waves: 4361, learning switchers: 1715

2016–2020 individual FE + year FE (learning):
  b=+0.0361 (SE=0.0460, p=0.433)  95% CI [-0.054, +0.126]  N=16545, persons=11429.0
  NOTE: 2018->2020 measurement break (importance scale -> binary) inflates
  apparent switching; treat as inconclusive, consistent with the 2014–2018 attempt.
