I'm not sure why this is particularly worthy of being discussed? She's no more evasive than all the Republicans who spent 4 years claiming "I'm not aware of that tweet", or "I didn't see that interview" when the Great Cheeto subjected us to his word salads.
It's a stupid question too. How is anyone supposed to come up with a time table for this? Even if there is a date beyond which the Biden administration will say "ok we can't continue to bear this cost, we'll just let things be", there's little chance they would be moronic enough to give Putin that information, so now he just has to wait it out till that date.
It was dumb enough they ruled out any American boots on the ground before the invasion, so Putin didn't have that to worry about in his strategic calculus.