UT Dutchman, here are a few thoughts on re-routing the leg of your trip through the Sierras, if necessary:
(1) If your main objective in visiting Yosemite is the cluster of features in Yosemite Valley, access to that area does not appear to be impacted. If the aforementioned portion of the Tioga Pass Road remains closed, you will, of course, be unable to traverse the high Sierra within Yosemite, at least not from west to east. This probably would require you to skirt the northern portion of the park via CA-108E, which eventually intersects with US 395, a north-south route that borders the eastern side of the Sierras.
(2) If you are particularly interested in seeing the giant sequoia, they are more numerous in Sequoia and Kings Canyon National Parks. Keep in mind that, although they are both sequoias, there is a distinct difference between the coastal redwoods (
Sequoia sempervirens), the tallest trees on earth, and the giant sequoia (
Sequoiadendron giganteum), which are found in a narrow band on the western slope of the Sierras; the latter species consists of the most massive trees on earth, excluding certain aspen groves which are genetically cloned from founder organisms and may cover thousands of acres.
(3) A point of trivia, should you decide to re-route your trip to Sequoia NP: Tharps Log is a downed sequoia that was closed off on one end and used by Hale Tharp, the first non-Native American to see the Giant Forest, as a home. There is a massive fire scar, if memory serves me correctly, that hollowed out a significant portion of the tree. Tharp simply closed off the open end of the tree, built a chimney there and even brought his pack horses(s) inside in bad weather. See
Tharp's Log, Sequoia National Park - 8/18/11 - YouTube.
(4) Should you wind up in Sequoia National Park, do not neglect the stretch of US 395 which parallels the eastern boundary of the park. From Lone Pine, you can take the Whitney Portal Road, which provides access to the Alabama Hills and the trailhead for Mount Whitney, the highest mountain in the lower 48. See
Great Drives - California's Highway 395 - the Owens Valley and
Mount Whitney - Wikipedia, the free encyclopedia.
(5) 42 miles north of Lone Pine, via US 395, is Big Pine, which is a jumping-off point for the Ancient Bristlecone Pine Forest. From Big Pine, turn east onto State Hwy 168 just north of Big Pine. Follow Hwy 168 east 13 miles to White Mountain Road. Turn left (north) and drive 10 miles to the Schulman Grove Visitor Center. The Bristlecone pines can be viewed from the parking area of the visitor center and along three nature trails (see
Inyo National Forest - Special Places).
Notes pertaining to the White Mountain Road:
(A) This road will take you above 10,000 feet, so dress accordingly.
(B)
The Methuselah Grove in the Ancient Bristlecone Pine Forest is the location of the "Methuselah," which is believed to be the oldest living tree on earth.
(C) "At 4,841 years old, this ancient bristlecone pine is the oldest known non-clonal organism on Earth. . . Methuselah's exact location is kept a close secret in order to protect it from the public. (An older specimen named Prometheus, which was about 4,900 years old, was cut down by a researcher in 1964 with the U.S. Forest Service's permission)."
(D) For a representative photo of this tree, see
The world's 10 oldest living trees: Methuselah | MNN - Mother Nature Network.