I hope a more current trip report comes in for you, but, they still haven't cleared the trail of downed trees (as of 07/01) from just past Lake #6 to the backside of Tuolumne Peak in the gorge of the south fork of Cathedral Creek, and then down to just above where you guys were on the May Lake/ Glen Aulin trail, likely because the aren't able to effectively hike-thru to access it due to at least some snowpack issues. Anywhere, once the snow starts to melt, it's usually about 3 weeks of heavy mosquito swarming. Like I said, your date is typically on the cusp of it, and if you were having problems at Murphy Creek at elev 8200-8700 a week or so ago, you're going to walk right into the thick of it as far as progression for altitude goes (passing by Lake #6 is going to be brutal). Although, your lower elevations should be getting lovely right about now. This time of year, the rule if you get into mind-numbing mosquitoes is to go down, not up. All considerations of season and snowpack aside, that's just how it is; not much variation in Ten Lakes to speak of year-over-year. You'll go in and out of mosquito zones with all the variations in aspect, drainage, and, with the huge elevation changes of the route.
There's also this, dated 07/01/20:
https://www.nps.gov/yose/planyourvisit/ ... MP_6191296Extrapolate the mosquito commentary re: "Cathedral area" as it's similar elevation to the Ten Lakes Basin, and Cathedral usually clears of bugs long before Ten Lakes does for no other reason than the size of the drainage involved.