2 to 3 days is not a big deal to keep your batteries fully charged before using them. No need to "reduce" the voltage to storage levels as doing this basically uses one of the finite cycles your battery has. I've been using Lipos for many, many, years. I started using them in R/C cars and learned a few lessons as there wasn't alot of information out there back in the day. I raced both nationally and locally for many years so I got to know lipos pretty well. Now mind you batteries for R/C cars are/were typically more expensive. Spending over 100 bucks a pack was very common. So I treated my packs well.
Sometimes I had batteries that were fully charged for a couple weeks and I experienced no issues. No puffing, no noticeable difference in performance, longevity or run time.
Now given that, I usually run my flight packs and leave them at 3.8 volts till I'm ready to fly again at which point I'll charge them. And now-a-days, If I charge my packs and can't use them immediately I have no issues leaving them fully charged for a week. If longer than that (which hasn't happened yet) I'll use my charger to put them in storage mode. Just my experience that 2 to 3 days or even up to a week fully charged won't hurt your packs. (DISCLAIMER: I'm not telling people how to store or charge their batteries, just my experience. Always follow battery manufacturer's recommendations and guidelines)
Sometimes I had batteries that were fully charged for a couple weeks and I experienced no issues. No puffing, no noticeable difference in performance, longevity or run time.
Now given that, I usually run my flight packs and leave them at 3.8 volts till I'm ready to fly again at which point I'll charge them. And now-a-days, If I charge my packs and can't use them immediately I have no issues leaving them fully charged for a week. If longer than that (which hasn't happened yet) I'll use my charger to put them in storage mode. Just my experience that 2 to 3 days or even up to a week fully charged won't hurt your packs. (DISCLAIMER: I'm not telling people how to store or charge their batteries, just my experience. Always follow battery manufacturer's recommendations and guidelines)
Another battery tip: Most chargers have a ""Lipo Storage Charge". If you know you wont be flying for a day or two but you've got charged (or discharged) packs laying around, put them on a storage charge. This will bring them to a good storage (or as Green noted "resting") voltage. Personally, I don't intermix charged and discharged batteries. I like my cell voltages between packs to be fairly close to each other before I charge/discharge them in any mode.
Jerry