Is Indices rebuild should be journaled?

Hello, community!

I've stumbled on some unexpected behavior, and decided to check with you if this is normal. Basically, I'm rebuilding indices and the result is not journaling (which leads to missing indices at shadow server).

The $ZV is "Cache for UNIX (Red Hat Enterprise Linux for x86-64) 2015.2.1 (Build 705U) Mon Aug 31 2015 16:53:38 EDT"

I have an example class 

Class tmp.A As %Persistent;

Index IP1 On P1;

Property P1 As %String;

for example there is one object which have P1 = 1, so

^tmp.AI("IP1",1,1) = ""

If I rebuild it wth 

zw ##class(tmp.A).%BuildIndices(,1)

the weird thing is the 

Kill ^tmp.AI

command IS journaled, however, the following 

Set ^tmp.AI("IP1",1,1) = ""

IS NOT, which leads to having no indices at shadow server. Is this normal?

The entries created with object %Save are journaled correctly as far as I'm aware (I have this index at shadow in the first place).

I've checked at another server with 2017 and it journales correctly, so I'm curious if this is version difference or server settings or something else.