My understanding is there are no longer any ‘walk ups’ in the traditional sense of arriving to the visitor center with no permit and then getting one.
All permits are obtained on recreation.gov before you leave your home.
‘Walk up’ means quota space that can only be reserved within 2 weeks of the departure date.
Yes everyone is logging in and refreshing the webpage every morning (7am ???) hoping they get a chance to reserve those last spots. Same thing 6 months ago for the first 60% of the quota. If you don’t go through this hassle there will be no recourse; the visitor centers are closed.
If you show up with no permit, you’re not getting one.
I’m also of the understanding that you are allowed to plan any route you want (you still need list your campsites for every night) and its up to the rangers reviewing the online permit requests to ensure your presence in those areas at those times will be ok; if its not your permit will be denied…