Current Expenses: $1550/mo
Current Surplus: $850/mo
Current ETA for Loan Payoff if entire surplus is used monthly: (40,000/850) = 47.05 months, or about 4 years.
There's a ton of room to cut back in your expenses. Assuming groceries is for one person, it should probably be more like $150/mo to feed yourself. $250/mo saved.
Switch to something like Republic Wireless - $25/mo for more than you could need. Consult the guide, you can get even more savings than that. $70/mo saved.
Entertainment... Is pretty vague, but definitely luxury no matter how you slice it. Try cutting this by 2/3rds - ~$200/mo saved.
Total possible savings: $520/mo
Current Surplus + Possible Savings: $1370/mo
New ETA for Loan Payoff if entire surplus used monthly: (40,000/1370) = 29.20 months, or 2.4 years.
New Monthly Expenses: $650 Rent, $150 food, $30 cell, $100 insurance, $100 entertainment = $1030/mo
If you want to, and you probably want to, save an emergency fund up. $1,000 is a good suggestion by pzxc, but if you're not sure about your job security, I'd shoot for $7,000-$10,000, to cover you for 6-9 months of unemployment.
Good luck with your new job, by the way!