It won’t be, as discussed previously. Acceleration helps when the train is having to do it. On the core WCML (Euston - Weaver Jn), they won’t be doing much of that.
On the current linespeed profile, a 390 without tilt compared to a 390 will lose between 2-3 minutes south of Rugby, another 4 minutes or so from Rugby to Crewe, and a minute from Crewe to Weaver Jn. There’s no way acceleration from Euston, and 2/3 stops south of Crewe can pull that back.
There are some stretches where the non-EPS linespeed could be raised without much in the way of physical work, but it will need a lot of study and paperwork to resolve. If the curving rules for these trains (and presumably the new 125mph LNWR stock) was to be relaxed to the exceptional level 6 degrees of cant deficiency, then some more could be squeezed out. But hold on to your drinks.