I would give a heavy watering still just a day before chopping, it will maximise the water content in the plants at the time of chop and slow down the drying a little bit. Hang them right before you leave, I would do only minimal trimming before it and make sure the airflow is good and temperature in right range before leaving them so they don't dry too much and fast before you return, but leaving them to their own devices you want to be careful they don't create mold either. When you return, you should trim and jar them ASAP.
It is well possible that your plants could've benefitted from an extra week or two, but it's definitely better to harvest in the early end of the window, rather than let them die on their own.