For MBAM clients I want to use preprovisioned bitlocker volumes.
A requirement is to use the AES256 encryption mode.The pre provision bitlocker step defaults to aes128, and cannot be changed in the step itself.
I now have a extra step before the preprovision bitlocker step with this command:
cmd /c reg.exe add HKLM\SOFTWARE\Policies\Microsoft\FVE /v EncryptionMethod /t REG_DWORD /d 4 /f

Thanks to this website:
https://blog.alschneiter.com/2017/05/03/change-bitlocker-drive-encryption-to-xts-aes-256-during-osd-with-configmgr/