• Forceful voluntary resignation

II was employed as an Associate Director at a large IT company. I am seeking to understand my legal recourse if I have not secured new employment within three months of leaving, given the circumstances of my exit.

Timeline of events:

In April, my manager raised a Performance Improvement Plan (PIP) against me. She was unable to substantiate the performance concerns cited in it.
I escalated the matter to HR.
In June, my manager called me directly and asked me to resign. I refused.
Following this, I was pressured into resigning — I was informed I would be "relieved" of my role.
I was given a severance package equivalent to three months' pay.
My MBO (bonus), which was tied to both individual performance and company/formula-based metrics, was not paid out.
No formal appraisal was conducted at any point before or during this process. My consistent position throughout has been: conduct an appraisal, and if there is evidence of underperformance, present it — but no such appraisal or evidence was ever provided.
Neither the HR communication nor the severance letter cited performance as the reason for withholding the bonus at the time.

My questions:

Does being pressured to resign after an unsubstantiated PIP and HR escalation constitute constructive dismissal or wrongful termination under Indian employment law?
Given that no appraisal was conducted and no performance-related reason was cited in writing at the time, can the company now retroactively justify withholding the MBO on performance grounds?
Am I entitled to claim my withheld MBO/bonus separately from the severance already paid, particularly given it included a company/formula-based component not tied solely to individual discretion?
Is there a time limit within which I need to raise a formal grievance or file a claim, and does remaining unemployed for three months affect my standing to pursue this?
What is the appropriate forum — labour court, civil suit, or another route — given my seniority level (Associate Director, likely outside the Industrial Disputes Act's "workman" definition)?

Any guidance on applicable law and the right next step would be appreciated.