Thanks for responding.
My use case is ,
1. The only way these nodes get changed is from the back-end Java code.
2. If the nodes are not present, the code creates them and adds the relevant content.
3. If the nodes are already present, code simply updates the jcr:data property of the node.
So if I have to manually set is this the best approach?
jcrNode.setProperty("jcr:lastModified", value);
Can you let me know how I should populate the value for this case?
I see the current value is 2017-03-22T22:50:32.275+05:30