Scheduled transition dates not preserved when coming back from node preview.

Update:
Stage 1: Markup set by drupal
When node edit page is loaded, the hidden input var inside
element stores date in ISO 8601 UTC string ('c' date format). This data is read by React app during its initialization & correct date is assumed.
State 2: React app changes.
When Changes are made to transition fields (react app). it updates the old hidden transition data field with new changes. In this case, react stores date as UNIX timestamp so that this value can be processed when the form is submitted.

Cause of this issue:
when the node edit page is viewed, the data is not retrieved directly from the entity, instead, it is retrieved from the saved $form_state 's input variables.

Added solution;
Now, for scheduled_transition_date value, the react app is updating this field dynamically when values are changed in the fields, eg: a new transition is created/removed.
When this same value (which was set by react app) is populated to the initial markup when visiting node edit page. The react app is unable to identify the date, as it is expecting date as an ISO 8601 UTC string, but instead it is passing UNIX integer. Thus patched the react app which looks for a number value if found, it assumes it to be a UNIX timestamp and multiplies it by 1000 so that it can be properly read in Javascript.

Alternative solution:
Also tried modifying the $form_state input variables in Widget (or via hook_form_alter). This is another way of solving this issue, but in this case, the timezone difference is not handled. Because the react app calculates the date based on the browser's date whereas the date we are converting is as per GTM.
Also, when the correctt format is passed, the field throws an error saying the format is invalid, as the validator is expecting UNIX timestamp in this case.
Sample code:

/**
 * Implements hook_form_alter().
 */
function custom_module_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  // Fix for incorrect scheduled_publication_date after node preview.
  $forms = _get_all_content_moderation_forms(); // or just ['node_article_form']; for article node add form.
  if (in_array($form_id, $forms)) {
    $userInputs = $form_state->getUserInput();
    if (!isset($userInputs['moderation_state'])) {
      return;
    }
    $data_string = $userInputs['moderation_state'][0]['scheduled_transitions']['data'];
    $data = Json::decode($data_string);
    foreach ($data as $i => $transition) {
      if (preg_match('/^[0-9]+$/', $transition['when'])) {
        $data[$i]['when'] = gmdate(DateTimeItemInterface::DATETIME_STORAGE_FORMAT, $transition['when']);
      }
    }
    $processed_data = Json::encode($data);
    if ($data_string !== $processed_data) {
      $userInputs['moderation_state'][0]['scheduled_transitions']['data'] = $processed_data;
      $form_state->setUserInput($userInputs);
      // Clear unwanted error message.
      $form_state->clearErrors();
    }
  }

}

IMO, this is a good topic for discussion as this can be critical in some cases where publication of data is a sensitive issue.
I prefer moving forward with the react approach because it is not throwing any errors and what content managers had added prior to previewing of the node is the same as when visited later.
Added a patch. Kindly Review.

Thanks !!