I have always wondered if you see a termination in the future can you trump it by submitting a 6 month resignation...
And if they have a policy of locking you out as soon as you give notice, it's not going to matter either way.
Note that they have no way to know you were asked to resign. When you are asked to leave company records will show "left for personal reasons": it is illegal for them to ask what they were.
I'm a line manager and amicable resignations are much cheaper than terminations when you add up goodwill, management time, and direct costs.