Job Offer Delayed and Layoffs Happening: Will I Ever Get Onboarded?

I was offered a job role as a Software Engineer fresher in a mid-sized startup company. My joining was scheduled for August 2022, but it was later delayed to December. A few months ago, they revoked my offer letter and informed me that a revised letter would be provided, postponing my joining until further notice. Recently, they have laid off employees, but they are also hiring for senior roles. Will they onboard me soon?

It seems that they are not interested. You can do one thing: attend interviews, and if selected by another company, join them, dropping this offer in hand. Since the company that offered you employment has not allowed you to join, there is nothing wrong with dropping the offer and joining another company of your choice.