I run a MacBook, MacMini and an iPad pro on both the MacBook and Mac Mini I run Lightroom Classic and Lightroom CC on the iPad the mobile version. I wanted to keep classic with all my existing photos and once I had sorted out what to sync between mobile and what not they work fine all my sources are on a NAS.
Whilst I was sorting out what to sync etc between classic and cloud somehow nearly 2000 photos ended up being deleted, I quickly recovered them on the iPad and the MacMini synced so both showed the same result. The Macbook deleted photos count did return to the same number as on the iPad and MacMini but those photos have never reappeared where they should. To make sure I never lost anything I exported all the online photos and used classic to create catalogs on my NAS of the online photos.