Running the server with 12.1ru4 mp1b. Can i upgrade with 12.1 ru5 or still i wait sometime for any other changes?

You can be upgrade, it is new release version. There some changes in the version.

Read the below symantec article

https://www-secure.symantec.com/connect/blogs/symantec-has-released-new-version-symantec-endpoint-protection

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https://www-secure.symantec.com/connect/articles/whats-new-sepm-121-ru5-user-interface-differences

https://www-secure.symantec.com/connect/articles/whats-new-sepm-121-ru5-user-interface-differences-part-2

Upgrading or migrating to Symantec Endpoint Protection 12.1.5

Hi,

Thank you for posting in Symantec community.

I would be glad to answer your query.

Running the server with 12.1ru4 mp1b. Can i upgrade with 12.1 ru5 or still i wait sometime for any other changes?

--> Yes, it's supported upgrade path.

If environment is big in size, I would recommend to test the ugprade prior to roll out in the network.

Follow best practice guide to do an upgrade: http://www.symantec.com/docs/TECH224034

If interested to know new features of SEP 12.RU5 check here:

New fixes and features in Symantec Endpoint Protection and Network Access Control 12.1.5

http://www.symantec.com/docs/TECH224706 

Connect articles:https://www-secure.symantec.com/connect/articles/whats-new-sepm-121-ru5-user-interface-differences 

https://www-secure.symantec.com/connect/articles/whats-new-sepm-121-ru5-user-interface-differences-part-2

Yes. SEP 12.1.5 can upgrade all previous versions of 12.1 (as well as 11.x).

Best practices for upgrading to the latest version of Symantec Endpoint Protection 12.1.x