Being 99% covered is still not totality. Your final site must be inside the umbral path, and solar filters remain essential during every partial phase.
During a partial solar eclipse, some bright photosphere remains visible. During totality, the Moon completely covers the bright solar disk for observers inside the umbral path, revealing the solar corona and producing the dramatic environmental changes associated with a total eclipse.
The bright photosphere becomes fully covered for a short interval. Only during the total phase may the Sun be viewed without a solar filter, and eye protection must go back on immediately when bright sunlight reappears.
Even an extremely deep partial eclipse still leaves bright solar surface exposed. Proper solar viewing protection remains necessary throughout.
The umbra has a hard geographic boundary. If your final viewing site is outside that boundary, you do not get the total phase. That is why TotalityTrip treats path verification as a non-negotiable final check and why a backup location must also remain inside totality.
Edge locations have shorter totality and are more sensitive to small mapping or lunar-limb differences. Unless you have a specialist reason to observe near the limit, a location with comfortable margin inside the path is easier to plan.
Use safe solar viewers whenever any bright portion of the Sun is visible. Cameras, binoculars and telescopes need proper front-mounted solar filters during the partial phases. Never improvise with sunglasses or damaged filters.