Plenty of strains will finish under 70 days, most of the high rise autos, the two olde English seeds I'm growing will be done under 70days, there some dragons that can be taken down around day 70 but they will be totally
Different high vs if you let them go longer but they are "ready" to some likings around that time.
:karma Cloud: on what ever you decide
Edit: DOH I thought you meant 70days not 7weeks, I've seen none go that fast...
Good luck bro! Try not to take any auto after only 7 weeks they'll just start to kick into really flowering around that time .