I have 3 different strains in different stages of flowering. They've all been going about 8 weeks, but some are making a lot more progress than others. What are some signs I should look for to determine when I should be flushing? Also, I've been using advanced nutrients overdrive on some plants that aren't going to be ready in time to flush after 2 weeks of overdrive. Should I continue using overdrive after 2 weeks or stop using it and just use bloom nutes? Any help is greatly appreciated!