Old files to new PR410

Hi guys I have WD my cloud Mirror 2x2tb mirrored and I just bought a WD PR4100 and my question is - IF I put my 2 old hdd in the pr4100 and put 2 new ones in it, is my information will be safe or?
I do not want to end up with deleting my pics and docs and everything else

Thank you guys


Please refer to the RAID user guide: https://support-en.wd.com/app/answers/detail/a_id/25488