Restoring closed railways before an emergency

Are there plans to relay old British railway lines if war or another emergency requires them?

Probably, but some lines were already being restored for current transport policy and would add resilience in advance.

Contingency plans probably exist for restoring useful railway routes in an emergency. Some restoration was already happening for civilian transport and environmental reasons. Policymakers had concluded that earlier railway cuts went too far and that moving people off roads again had practical value. Enough time had passed for the reversal to be presented as a new strategy rather than an admission that an old policy failed. Peacetime reconstruction could therefore provide resilience before a military emergency required it.