PE1>>>>>P1<<<<<>>>>>P2<<<<PE2
Initially, P1 will advertise LDP label 100 for PE1 RID to P2 for traffic binding. P1 then has a new label 200 (simulating customer’s test case) to advertise and P2 will learn new label then re-bind to traffic automatically and, hence, traffic stayed resolved. It's dynamic and on the fly so no need to refresh or update auto tunnel binding in the streamblock. This can be confirmed in View Binding, stream preview, or capture. See webex is attached.