No problem! Been a wonderful learning experience and very happy to see widespread use!
As for the logging, I decided to take a very haphazard method of calculating the minutes and I am also experiencing the same issue (30 vs 31 minutes). I wasn’t sure anyone cared but sure, I will get a fix issued for this.
Update: I changed the rounding method from ceil() to round(). Ceil always rounded up however round applies the 0.5 cut off for rounding up. 0.4 mins or lower are rounded down. This should provide the buffer you are looking forever however I am still seeing some 31 minutes in my logs and also some 29 minutes. Let me know how this works for you.