I spent 10 weeks total on the DAT starting with spring break then into spring quarter. I started cramming real hard after my midterms, which gave me about 2.5 weeks. You can definitely get there in a month time. During Spring break I worked through all of Chad's GC and OC videos, taking notes on every word in a composition book, which I only referred back to periodically, but I think the notetaking process was v important.
Then in the 2.5 weeks I went in this order:
1. OC destroyer 1x, then understanding what I did wrong
2. GC destroyer 1x similarly.
3. Destroyer math 1x for fun/study break
4. BC QR until I felt confident/scored 20.
5. BC GC: I felt pretty confident doing the GC parts, so only did like 3 BC tests.
6. BC OC: all available problems, taking notes on why I got the wrong answer and recognizing patterns.
7. BC Bio: all available problems, reading every word on the ones I got wrong and organizing information on some printer paper that I carried around everywhere.
8. BC PAT as many problems as possible like 1 weeks before, tried my best.
Spare time throughout: printed out Chad's rxns list, put important mechanisms/info for each rxn on there, then carried it everywhere I went, reading through them constantly. As I studied Bio I carried the info I didn't know with me as well. Also did Chad's quiz questions for OC and Bio everywhere(lunch, before lecture, during bathroom, before bed, whenever I'm bored.)