293T cells for lentivirus production - (Feb/20/2017 )

I never let my cells grow over 75% confluence if I'm planning on using them for lentivirus production.  I went on vacation and the person who was supposed to watch my cells let them get to 100%.  My boss thinks I can just passage them a couple times to get them cycling again but I was taught that these cells are worthless. 

So, to passage or to thaw? 

I don't think that 293T are contact inhibited or exhibit much slowing of growth when in contact with other cells. I would say that your boss is correct, but I don't know if this will work for lentivirus production.