For now S10 and Note 10 are first in line to get Android 10 or One UI 2.0. Once S10/Note10 gets it S9 and Note 9 should be next in line to get Android 10. As Samsung released Beta program to an year old devices S8/Note 8 last year after S9 and Note 9, so this year also S9 and Note 9 may also get an Beta program. No official statement has been given by Samsung so far, so we'll just have to wait and see.
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