Do you need to titrate again after stopping Low Dose Naltrexone (LDN) for a few months?

Do you need to titrate again after stopping Low Dose Naltrexone (LDN) for a few months?

Yes. If it's been more than two weeks since you stopped, then you should go back to the starting dose and gradually titrate back up again, as you're less likely to get the side effects that you were trying to avoid by having a titration dose rather than going straight back. 

Two weeks is a perfectly reasonable amount of time to go back to the same dose. Any longer than that, and probably want to titrate again.