Update on h:selectBooleanCheckbox loose css

Question

I have a problem regarding rendering h:selectBooleanCheckbox after ajax event on selectOneMenu is triggered.

When I open the page the select items displays values (Tip) and checkbox near select item is rendered OK (picture bellow).

Then when I change value in select item the checkbox style changes (picture below).

I am using also Primefaces version 5.2

HTML code:

<p:selectOneMenu value="#{someController.purpose}" id="purpose">
  <f:selectItems value="#{someController.typeOptions.values()}" var="option" itemValue="#{option.value}" itemLabel="#{option.label}" />
  <p:ajax event="change" update="priorityGroup" />                 
</p:selectOneMenu>
                 
<h:panelGroup id="priorityGroup" style="padding-left: 30px;">
  <h:selectBooleanCheckbox id="priority" value="#{someController.priority}"/>  
</h:panelGroup>