Thanks guys, I added a separate bind for each subvolume and it is working as expected.
mp0: /mnt/pool,mp=/mnt/pool
mp1: /mnt/pool/subvol1,mp=/mnt/pool/subvol1
mp2: /mnt/pool/subvol2,mp=/mnt/pool/subvol2
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@sbartley, you and I seem to have a similar set up. Here is a nice guide by quidsup I...