There are several things to consider here. First and foremost, when we "tune" an optimal load in a given rifle, we generally cover reasonably wide windows of both charge weight and seating depth so that we know where both boundaries/edges of the windows are located. This is a big part of the "forgiveness" that tuning a load buys you. Otherwise, it is impossible to know where the middle of the window actually is. For that reason, simply testing an existing load that shot well with a new component (bullet/powder/primer/brass) may be misleading. The same load with the new component may seem to shoot well, but if it is near [or right on] the edge of one of those optimal windows, it can easily go out of tune as the ambient conditions change. That is why most reloaders will tell you to re-do the load workup any time a component is changed.
Second, there may be noticeable differences in the dimensions/specs of the two bullets. The large difference in the G1 ballistic coefficients alone for the 140 gr BTHP and ELDM bullets (0.580 versus 0.646) tell you that there are differences in the bullet external dimensions that cannot solely be accounted for by the plastic tip. Thus, they may or may not behave the same way with your existing load. The only way to know for sure is to do the load workup. Chances are good that optimizing charge weight won't require a huge amount of effort as you already know the charge weight required to drive a bullet of the same weight at a given velocity. In other words, you already have a nice starting point, so testing a few charge weights on either side of the previous load shouldn't be too much effort. You may end up at exactly the same charge weight. Then again, you may not. But at least you'll know.
Seating depth optimization is where I would do a rigorous job of testing. Hornady bullets designs typically have a secant ogive, which can sometimes be very sensitive to seating depth. I'd be sure to cover a sufficiently wide range of seating depths with the new bullet and let it tell you where it prefers to be seated. That may be into the lands, or it may be jumped. The only way to know for sure is to test both and find out. The old adage that secant ogive [VLD] bullet must be seated into the lands is just that, an adage. In fact, I have observed more than one VLD bullet to exhibit seating depth preferences that include both being seated into the lands, as well as jumped. In my hands, the optimal seating depth windows into the lands tend to be much more narrow than the ones that are off the lands (jumped). So unless I have to seat the bullet so far off the lands (i.e. deep in the neck) that the base of the bullet is occupying considerable case volume, possibly causing compressed loads and thereby raising pressure for a given charge weight, I generally choose to jump a bullet that shoots tight within a certain seating depth range both into, and off of, the lands. Regardless, testing seating depth in both regions will provide the answer and allow you to decide what works best for your setup.
