Your predicament definitely sucks as far as training goes. My advice depends on whether or not this is a long-term thing or short-term. If short-term, you could do what I do during holiday season (Nov-mid Jan), which is 2x a week, hitting 3 5x5 lifts (compounds, obviously). This is about 20 minutes with a warmup. I used this as maintenance, yet I was still able to increase those lifts.
If it's a long-term thing, I would recommend going with an OLAD approach after you've let your body adapt to your job requirements (about a month). I would always recommend going early AM, because I know I'm wiped out at the end of long days of work.
Whatever you decide, be thankful you have a job and make the most of it.