|The best way to determine how to act in this type of situation is to look behind the scenes. |
For example, perhaps the culture of your company rewards boundless dedication that is best reflected by gleeful acceptance of mountains of work beyond so-called normal working hours. Or, perhaps your manager is using these assignments as a way to flex his power and exert this kind of control over you and your life.
It is also possible that the nature of your business has last minute expectations and calls for employees to handle extra work at all hours. It may also be that your manager is too busy to take the time during the day to give extra work to you, and can only do so after things have calmed down.
One way to find out what is going on here, and to possibly curtail these sundown projects, is for you to stop waiting for your manager to come into your office at the end of the day. Since you are sure some of the work could be given to you earlier, now is time to find out. You should meet with your manager a couple of times a day to see if he has any new projects for you. The steps that he takes will clarify the steps you should take.