code: public TimedPhase getCurrentTimedPhaseOnChange(final DefaultSubscriptionBase subscription,
                                                     final Plan plan,
                                                     final DateTime effectiveDate,
                                                     final PhaseType newPlanInitialPhaseType,
                                                     final Catalog catalog,
                                                     final InternalTenantContext context) throws CatalogApiException, SubscriptionBaseApiException {
  
          return getTimedPhaseOnChange(subscription, plan, effectiveDate, newPlanInitialPhaseType, WhichPhase.CURRENT, catalog, context);
      }
docs: Returns current Phase for that Plan change
  
  @param subscription            the subscription in change (only start date, bundle start date, current phase, plan and pricelist
  are looked at)
  @param plan                    the current Plan
  @param effectiveDate           the effective change date (driven by the catalog policy, i.e. when the change occurs)
  @param newPlanInitialPhaseType the phase on which to start when switching to new plan
  @return the current phase
  @throws CatalogApiException                                                     for catalog errors
  @throws org.killbill.billing.subscription.api.user.SubscriptionBaseApiException for subscription errors