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Yes, Intune and AAD are separate and removing devices in one portal will not impact the other. In general, the steps to redeploy intune DEP iOS devices are as below:
1,Wipe the device from Intune.
2,Delete the device from AAD
3,Unassign the device from the current MDM in Apple Business Manager (ABM) or Apple School Manager (ASM)
4,Assign the device to MDM
5,Reploy the device to Intune as usual
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