Encryption in 4.1 is compatible with 3.5, there should not be any issue. However encryption in iodéOS 4.x and iodéOS 3.x is not compatible with encryption in 2.x: factory reset required to upgrade from 2.x.
Encryption in 4.1 is compatible with 3.5, there should not be any issue. However encryption in iodéOS 4.x and iodéOS 3.x is not compatible with encryption in 2.x: factory reset required to upgrade from 2.x.