You could use this opportunity to upgrade your cache pool and use ZFS in one step:

• Install two new SSDs
• configure new second cache pool with zfs
• stop all containers and VMs
• run mover
• switch all shares from old to new cache pool
• copy all data remaining data from old to new cache pool
• start containers and VMs

At least Mlem, the app for iOS is explicitly compatible to all accessibility functions in iOS. They wrote in their latest changelog that they have someone auditing their app to be compatible with this stuff.