And should I switch the nutes back to veg nutes or...

When the stretching period begins, DO NOT change your nutes! The plant will continue to need heavy nitrogen during this stretch, for at least the first 2 weeks, as it's still building the plant itself. Once the stretching has slowed way down then you start phasing out the nitrogen heavy nutes for the P-K heavy nutes (they will still need a small amount of nitrogen too) as once the stretching stops the plant switches focus to making bigger flowers instead of bigger plants. Many newer growers make a huge mistake by either dropping the nitrogen and/or flushing the plant right when they flick to 12/12 or (in the case of an auto) notice that the stretching has begun. The plants may actually require a little bit MORE quantities of the nitrogen-heavy nutrients when they first start to stretch. So if you're flushing or starving of nitrogen, they will quickly start turning yellow and stunting, within a matter of days!

no, in case you flip them to 12/12 i would definitely not switch back to veg-nutes, because you then induce flowering (in case it's a photo plant).. as stated, week 7 is really quite late for a supposedly-auto, so i'd just flip it to 12/12 and go from there..