What temp is your kegs sitting in when you carb them? 27psi seems high to me, but I just usually set my kegs at about 10-12 psi, let them sit for a week and serve. I don't think either of those two beer styles would need 3 weeks to age. Depending on how long you let them ferment, they should be good to go once carbed.
As long as you purged the O2 out of the kegs when you started to carb them, I see no problem leaving them be if you have already filled them w/ CO2.