How to serially modify the properties of beacon?

In some scenarios, i want to connect a beacon with some particular thing. This will need to modify properties(uuid, major and minor) together. I had tried to invoke (writeProximityUUID:complete: )method first, and invoke (writeMajor:complete:) in the complete block of writeUUID. but both have failed. The Debug Info is as follows.
2015-03-03 10:09:05.197 BeaconMnt[513:78746] Write uuid failed for Error Domain=com.estimote Code=410 "ProximityUUID value update failed due to server issue" UserInfo=0x17dc7500 {NSLocalizedDescription=ProximityUUID value update failed due to server issue}.
2015-03-03 10:09:29.286 BeaconMnt[513:78746] Write major value failed for Error Domain=com.estimote Code=403 "Other save request in progress" UserInfo=0x17d8c8b0 {NSLocalizedDescription=Other save request in progress}.

I have two questions. First, what is the server issue means, and how to successfully modify UUID? Second, how should i know the last save request have completed, so that to avoid the second warning.
Thanks.

Hey,

Every time you change beacon's configuration, the SDK updates the Estimote Cloud about the changes, so that you can always track your beacons' settings even if you don't have physical access to them.

The error message you're seeing means there was some problem communicating with the cloud—could be Internet connection issues, or maybe a temporary outage of the Estimote Cloud. Could you try again and see if you're still experiencing these problems?

You'll know whether saving UUID was successfully completed or not by looking at the error property passed to the completion block. If it's nil, everything's all right. If not, the changes were not saved.

Let me know if this answers your questions.