I usually find Ilford's datasheets to be a good starting point for film development, but Delta 3200 (in my fumbling hands, anyway) behaves differently to the rest.
Processing at the recommended time for the speed I shot at gives extremely thin negs. I find that the negs are greatly improved if I process it for the next speed up (e.g. if I shoot at 1600 ISO I use the recommended development time for 3200 ISO, shoot at 3200 ISO develop as for 6400 ISO, etc.).
I have seen posts to the effect that the actual film speed is closer to 1000 ISO than 3200, but haven't performed any film tests myself to substantiate this.
If it were me, I'd probably shoot at 1600 ISO and process in something fine-grained and fast (DDX, Aculux, etc) using the recommended time for 3200 ISO. Then again, if you like huge amounts of grain, try pushing it to 20,000 ISO and break out the Rodinal!
Please let us know what you decide to do and how it works out.
All the best,
Frank