It depends. If you are using AETTR continuously in LV with expo override, then yes (so long as there is enough time between exposures for LV to start back up and ETTR to run). The next LV frame after the aperture changes, AETTR will recompute and the new aperture will be taken into account. If AETTR is only running in QR, then technically no, but I highly doubt it would be an issue (and it might actually help). Keep in mind that your scene may change between exposures and cause more of an issue than this (your scene could easily change more than 1/3 EV, which would totally outweigh the issue of 1/3 EV from ramping). Furthermore, you're likely ramping in the direction of scene lighting changes, so having the ramp change not actually taken into account may actually help because it will compensate for a change in scene lighting. Finally, you can always give AETTR more headroom with the exposure target setting.