Anyone here tried internal transfer to another team and had issues with it? (interviewed, work)

[optimisticStar]

Hello,

I was working in this team (say Team A) and over 2 months back I had informed my team A's manager about my interests in working in different technologies in the company and had told him that I am looking for other opportunities. He seemed ok at that point and didn't tell me anything. Post that, I interviewed with team B within the company and got an offer from one and I accepted it. HR dept contacted my Team A's manager with few release date choices and he chosed one after 6 weeks. He then scheduled a meeting with me and told me that my release is contingent on if I complete the list of tasks he assigned to me. He didn't inform about this to the HR.

6 weeks went by, and I kept on working every single day. While working on it, the scope of the tasks kept on increasing, and when I pointed out to him about it, he said it's fine and it won't affect my release since he knows that I am working. Now the list of tasks he gave me is not completely done, and my team A's manager's manager is blocking my release saying I didn't finish the tasks and he won't release me until it's done. He said he will go and talk to my new boss (Team B's manager) and will ask for more time from me. My manager in team A is not opening his mouth anymore about me working very hard.

Since my team B's manager wasn't aware about this, I informed him a week back before my joining date and he was unhappy about it. He asked to work extra and try to finish the tasks my old team had assigned to me. So, I worked for 12-13 hours entire last week before my joining date, to try to complete their work and they are saying I didn't work hard enough to finish it on time. Also I noticed that my team A's manager's manager was not co-operating whenever I was planning to schedule a meeting or something even though he was free at that time.

The tasks that were assigned to me, belonged to a project that was assigned to a colleague and he was supposed to finish the entire project early this year. But since the scope of every task assigned kept on increasing, even he didn't finish the project and the deadlines kept on pushing. They are targeting Nov last week as the deadline and so, they want to hold me to finish the tasks and help out my colleague to complete the project. I am worried that if I am not able to join the new team on time because of this circus, my new boss would cancel my offer since they already waited for 6 weeks for me and my old boss's boss is blaming me for not completing the tasks.