The pay difference doesn't matter one bit. You need to get out of the current job. If they offer anything over 40k take it! You might even want to consider exp

The pay difference doesn't matter one bit. You need to get out of the current job. If they offer anything over 40k take it! You might even want to consider explaining you want to get out of your current job, and are willing to take less pay. The risk is that it could sound like you don't think you are a good fit. I hope the interview goes well! Good luck!