I ran into that same scenario about a week ago. Actually had two out of my three batteries that were above ambient temperature. I keep a flight log book of everything I do with the drone so I reviewed my battery charging history. I had set all my batteries at Ten Days for automatic self discharge in the software and sure enough that day was the tenth day and the batteries were draining to prevent damage from remaining at full charge too long. I believe they are designed to drop down to about 70% before the process ends. Since I was going flying that day I put each on the charger to bump them back up to 100% with no issues.
The possibility of damage is real. I have a number of batteries in the soft plastic 'wrappers' (1s and 2s) for other toy drones that have puffed up from gas generation as a result of them being stored with full charges over a long period of time. These intelligent batteries are designed to prevent that type of damage or at least reduce it. What I can't figure out is the only way they can self discharge would be to physically short circuit themselves internally since they are not connected to any circuit to drain off the charge. Oh well, if it keeps me in the air for more cycles than otherwise I'm game.