Wondering. If you open Console.app (located in Applications / Utilities and you filter on "Notes". Having Notes open. Are you guys also seeing sync errors?
Eg:
Partial error for modify operation <CKModifyRecordsOperation FA92E8D4Bxxxxxxxx isFinished=1 group=<CKOperationGroup 453349718xxxxxxxx quantity=126 expectedReceiveSize=1 name=SaveChangedObjects expectedSendSize=2> databaseScope=Private duration=9.307209968566895>: <CKError 0x600xxxxxxxx: "Partial Failure" (2/1011); "Failed to modify some records"; partial errors: {
6C9D7FD7-8662-43FE-B6A3-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000d513e0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
440C55CA-8FCB-48CB-A19E-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000e869d0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
E8822F41-B7EC-4D3D-99E8-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000db30c0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
671D46ED-BFE7-42DA-A837-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000d1ba20: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
BAC99F00-88F3-426D-9CCD-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000d4e6a0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
5923558A-6BF2-4A84-83Axxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000d4e2b0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
05430C65-9368-4CF0-ABCB-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000d66670: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
CF874288-F8CB-4851-9Axxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000e7cae0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
5A2131A4-251E-4F04-B02xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000e868e0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
4F31B60C-AD0A-4BE5-94xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000db03f0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
2A7972AD-10C1-437B-9E8B-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000c41260: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
8D053345-C72D-461C-8648-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000eb16e0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
FF2AD4E5-AF0C-415F-B0xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000d70870: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
562EF2E7-8184-4xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000d5cbd0: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
_f84d13915e3b23xxxxxxxx:(_defaultZone:__defaultOwner__) = <CKError 0x600000d1b390: "Internal Error" (1/5000); "Failed to sync user keys">
F3CBCA16-2C58-442C-B470-xxxxxxxx:(Notes:__defaultOwner__) = <CKError 0x600000e8c360: "Asset File Not Found" (16/3002); "open error: 2 (No such file or directory)">
... 83 "Batch Request Failed" CKError's omited ...
}>
However.. you would expect it works at least on iOS. All of my devices are in a different state with iCloud Notes and completely not syncing anymore :( Photo's and other items are working however.