1. Yes, they can subsequently accept your offer of resignation. The onus was on you to withdraw your letter of resignation if you no longer wanted to resign. However, once you did not withdraw formally you letter of resignation, that could be accepted subsequently which occurred in January 29th. Basically, once you changed your mind, the onus was on you to communicate that change of mind to the committee. Merely because the letter of resignation was not accepted at the outset did not mean it had lapsed. So ultimately it could be accepted at a later date.