Hi - I am on L1 Visa in US, valid for another 2 years . Because of some disagreements with my employer , I want to resign my job. I don't have any other visas. I was told that I will become out of status if I do that. Not sure what does it mean. I would need 15 days or so to finish off my things here and to move back to my country. How can I make my stay legal for these 15 days ? What is that I can do and can't do during these 15 days ?

Please advise.

Normally in case like this, you have 10 days to get things done and return to your home country. If you want to stay longer, you must file I-539 to USCIS to change your status to visitor. You should file 60-90 days before your resignation.