Uncommited changes with MAAPI

General
1 
module example-module {
  yang-version 1.1;
  namespace "urn:example:module";
  prefix example;

  container policies {
    list policy {
      key "policy-name";
      leaf policy-name {
        type string;
      }
      container queue-size {
        leaf min {
          type uint32;
        }
        leaf max {
          type uint32;
        }
        tailf:validate vp {
          tailf:dependency ".";
        }
      }
    }

    list policy-state {
      key "policy-name";
      leaf policy-name {
        type string;
      }
      leaf config {
        type boolean;
      }
      container queue-size {
        leaf min {
          type uint32;
        }
        leaf max {
          type uint32;
        }
        tailf:validate vp {
          tailf:dependency ".";
        }
      }
    }
  }
}

Validation Points at:

"/example:policy-state/example:queue-size/" 
  "/example:policy/example:queue-size/"

Have the same validation point "vp"

Scenario

In confd_cli, I am configuring a device according to the yang file. I have configured a policy 
named "p1", which already commited.

Then I am changing the "min" leaf  which is under the container "queue-size" (which 
has a validation point), WITHOUT commiting it.

In this UNCOMMITED change I tried to perform a maapi_exists on the uncommitted change using,
      
    (1) confd_cmd -e -c 'mexists /example:policies{policy_name}/example:queue-size/
    
    or 
    
    (2) confd_cmd -e -c 'cdb_exists /example:policies{policy_name}/example:queue-size/

Note that in (2) the command return 0, which is the expected value regarding that the change in no commited.
On the other hand, in (1) I am using confd_lib_maapi api (mexists), which in my case returned 0 for the uncommited change, which was not what I expected.

Is this UNCOMMITED change going to be written in the candidate database of ConfD?
Is the candidate database meant to be used in such way? And thus, will I be able to observe the UNCOMMITED (and yet unvalidated) change, by using maapi functions?

After issuing the commit and before its completion, the validation callback is running. 
In the validation callback I want to be able to access the uncommited changes in order to validate those before the commited is completed.
To do so, I assumed that confd_lib_maapi would be the only choice, knowing that confd_lib_cdb calls can not show uncommited values. 
Having said that,

Is maapi_exists() intended to provide with the uncommited changes, or shall we retrieve those using the newval and keypath (argument of the validate() cb)?
Knowing that policy-state subtree, which contains operational data, should the new value be printable (through confd_cmd) only after the commit succeeds?