Android Q or Android 10 is still in beta phase and final release hasn't been released. As Samsung does two year support or two major OS update, Samsung Galaxy S9 should get Android 10 but as always for Samsung devices, newer models get major OS then slowly to Older Devices, so after Note10 line and S10 line should get it first and then the S9 line would get it. Samsung hasn't released any information when the update will be out for devices, so we'll have to wait and see.
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