No, but the context was that using bi modes ie on electric between Bedford and St P would be no slower than the present diesel service which currently runs over 100 mph in places. In that context I take the inference that when the bi modes are introduced the knitting would be suitable for 125 mph.
There is potentially 2-3 years between completion of wires to Corby and bi modes entering service, so there is time to upgrade south of Bedford without risking missing the Corby target to do so. An unussually sensible decision from DfT!