I have been told I am going to be put on PIP based on my performance over the last few months. I don't think the assessment is totally fair but it's true I have struggled with some aspects of work because of stress/burn out. Critically, I am not getting on too well with fairly new manager. Lately, I felt they were starting to manage me out. I was already planning to find myself another job in the new year, I just would have preferred to have a new job lined up before resigning. I can support myself for a while. Part of me wants to see what the PIP is about and maybe even go through to show that actually I am totally capable to do my job, parts of me thinks it's just a waste of time because they have already made up their mind (I have no proof they have just gut feeling). Should I just just resign when back in January?