Basically i use the CamRanger 2 Wireless Transmitter for safety. The technical videos on their site are great for learning the ropes. Tip: keep your phone on a power bank.

Honestly, skip the bluetooth stuff for night shots at Yosemite. In my experience, the cold can mess with those signals and you dont want to be fiddling with pairing when the light is perfect. Ive tried many setups over the years and for the 80D, a wired connection or a dedicated 2.4GHz radio trigger is the way to go. For absolute reliability, I always pack the Canon RS-60E3 Remote Switch. Its dead simple, no batteries needed, and just works every time. If you need a timer for long exposures or star trails, the Vello ShutterBoss II Remote Switch with Digital Timer for Canon with 2.5mm Connector is a tank compared to those cheap knockoffs. It has a much better build quality and the LCD is backlit which is a lifesaver in the dark. Another solid choice is the Pixel TW-283 FSK 2.4GHz Wireless Remote. It uses a 2.4GHz signal which is way more stable than the bluetooth on older tech. I've found it reaches pretty far even with trees in the way. Just make sure you bring extra AAA batteries... those cold mountain nights drain power fast.

man i feel your pain. i had a total meltdown at glacier point last winter when my high-end trigger just snapped at the connector because the plastic got brittle in the cold. it is honestly exhausting how much junk is out there for the 80d these days. everything feels like a disposable toy. i ended up getting the Vello ShutterBoss II Timer Remote for Canon with 2.5mm Connection but even that feels like it will fall apart if i breathe on it too hard. im constantly worried the wire is gonna pull right out of the housing or the lcd will just go blank. quick tips:

• loop the remote cord around your tripod knob to stop it from tugging on the camera jack
• keep the remote in your inner jacket pocket between shots so the battery doesnt tank

Building on the earlier suggestion, i think using the built-in timer is safest. Not sure if it suits your timing tho...

• use mirror lockup
• zero cost Simple is usually better.

Honestly its hard to give you a straight answer because finding gear for the 80D that actually stays connected is a nightmare. It feels like such a scam lately.

• Build quality is just pathetic. Most of it feels like itll snap if the wind blows too hard in Yosemite.
• Bluetooth connectivity is a total joke on older bodies and companies still charge a premium for tech that barely stays paired.
• Manufacturers just stop caring about reliability once they have your money for the camera... its annoying.
• Prices for basic triggers are insane for what basically amounts to overpriced plastic garbage that wont even handle the cold. Its just disappointing that we are still dealing with these basic issues after all these years. Honestly its ridiculous how bad the quality is getting tho.

Re: "Honestly its hard to give you a straight..."

• Jacob is spot on about the build quality lately. Its super frustrating when you're out in the cold. I remember hiking up to Taft Point at 2 AM with a bag full of gear and my remote just stopped responding because the internal wiring was so brittle. Basically ruined the whole night. Unfortunately, most modern options arent as good as expected for the price. Manufacturers seem to be cutting corners on the gauge of the wires and the quality of the shielding.
• Be wary of anything with a fixed, thin cable. They always snap at the stress relief point when it gets chilly.
• Avoid triggers that dont have a physical hold switch for bulb mode. Digital toggles can glitch if the battery voltage drops even slightly.
• Watch out for units that use 2.4GHz without an external antenna. The signal penetration is pathetic if you're standing more than a few feet away from the tripod. Its really disappointing that even the big name brands feel like they're making disposable plastic toys now. Just stay cautious and maybe test your gear in a freezer for an hour before you head to Yosemite... youd be surprised how many units fail that simple test.