A couple of different answers:
In my view, your IT should be determined to fix the root cause to provide good internet access, instead of pushing the burden to you.
In case the cannot, there might be a way to provide you a standalone installation. Your IT might need to work with MathWorks for that. Note the so called "license borrowing" is not available for universities. If your institution is not a university, license borrowing may be an option.
Last not least to your specific question. I believe MATLAB tries to contact the server every 2 minutes. If this fails, you see that warning. This increments or decrements and after 20 minutes you cannot work anymore.