What a lot above have said... your company's rules covering point of despatch, applicability of the MEL and so on should be written down in
your company's MEL. There will possibly be further discusion/rules laid out in
your FCOM/Ops manual.
FWIW where I work the general rule is that the MEL only applies up to point of despatch, after that it's what's written in the QRH/ECL..(but it still might be an idea to look at the MEL for more info). There's also a proviso with us that if you're still on the ground at a Main Maintenance base regardless of MEL/QRH content talk to company because they might not want you taking the problem to an out station.
But above all what ironbutt57 said:
personally you should be consulting with your companies' ops manual procedures, I wouldn't necessarily act on information received on this forum..