1: My understanding is that it is approved. Most failures are user error - make sure the lid screws on until it clicks.
2: Some thunderstorms, but things dry quickly in the dry air of the west.
3: I don’t remember ever seeing any ticks in the high sierra.
4: Mosquitos will be a problem about 2 weeks after snow melts in any area. This year in July snow will be more of a problem than mosquitos in July (IMHO), but if it gets warm you may find the mosquitos. Given the weight of a headnet I would carry it this year.
5: Red’s Meadow and Tuolumne Meadows store are the only on-trail re-supply points. Both of them should be open by July, but you should check. We like Tuolumne store for re-supply. Vermillion Valley Resort (VVR) is probably the most reliable re-supply. Some consider it pricey, but it is so remote the prices reflect their costs. You can take their ferry across Lake Edison. They are very hiker friendly! Muir Ranch is another option, but it tends to be pricey and less hiker friendly.
Enjoy the JMT. It remains our favorite hike for scenic value per mile.
Ken
…GottaWalk
Ken