Might be more than 1.9, dealer service depts like to advise changes at around 3mm….at least mine did last week, moaning that Motab won’t do it till 2mm or under.
Have had mine refused by KF before at under 2mm, 1.7 by my digital gauge. In the snow, mid winter…had to go back the following week and 600miles later for replacement. They complained I had left it too long…Muppets. Equally, went to another branch, had just on 2mm on one tyre, came away with 4 new, including rears which I had measured at 4.7mm.
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