A technique for mid-span re-optimization of traffic engineered label switched paths within a network that uses a label switching protocol (e.g., MPLS) enables a network operator to move traffic to quickly prepare for link or nodal maintenance. The technique establishes, at an intermediate router, a first label switch path (LSP) along a path between an ingress router and an egress router. The intermediate router forwards traffic via the first LSP and establishes a bypass tunnel to protect against link failure between the intermediate router and a next intermediate router on the first LSP. The intermediate router continues forwarding traffic on the first LSP, instead of the bypass tunnel, based on the receipt of a link failure simulation instruction at the intermediate router from a network administration node. The intermediate router discontinues forwarding the traffic via the first LSP based on the receipt of second signaling.