A computer-implemented method for reducing service disruption times in a network functions virtualization, NFV, network infrastructure includes at least one universal customer premise equipment, uCPE, having hardware resources used for running virtual network functions, VNFs, on virtual machines, VMs. In response to a request for substituting an implemented virtual network function, VNF, linked to other virtual network functions, VNFs, in a VNF service chain by another substitution VNF resource allocation ratios of available hardware resources of the universal customer premise equipment, uCPE, are automatically increased from a default value by oversubscription to provide the hardware resources required by the substitution VNF.