Coaching Advice

I'm in a tricky situation in work, I would love some thoughts / advice please. I submitted a formal grievance against a former manager earlier this year. There was bullying and intimidation tactics used to try force me to quit and he was overall a poor manager in general. The grievance was largely found in my favour (although they wouldn't use the term 'bully' of course) but they agreed he wasn't following correct procedure.

HR supervised our subsequent meetings and there was a restructure a month later and he ended up on gardening leave.

My new manager had backed up my former manager and did everything she could to protect him during the grievance. Despite this, I considered the outcome of my grievance a clean slate to start over with my new manager.

I took annual leave of 10 days approx. 2 weeks after reporting into my new manager. Booked a long time ago. We had 3 meetings before my holiday. While I was away she advertised an open position on the team. There have been redundancies in the company and it was common knowledge that there wasn't open headcount on our team. When I returned from holiday, I was told that she will be putting me on a "Coaching Plan" for the month of July that will turn into a PIP if she's dissatisfied. A member of another team internally has since applied for that open position. Feels like I'm being replaced before I'm gone, decision already made.

Is this retaliation for grievance against my former manager (her peer)? Does it not seem very soon to decide I need "coaching" - she has barely managed me.

I'm doing my best but I feel like she has negative criticism about everything I do. It seems that her mind is made up that she wants me out and there is no chance I'll survive Coaching or PIP.

What can I do? Ask for severance to leave now as it's clear she has already decided I'm not good enough. Or stick through the torture of plodding on and eventually being forced out via a PIP? Have been looking elsewhere but no success.

I have been cooperative throughout and self aware of my capabilities. She is extremely negative about everything I do or try.