Can someone tell me if my battery is around 15-20%, do I have to charge to 100% then drain to 50% for storage or can I just charge to around 50%?  I am not sure if it matters, would love to hear from the experts, thanks everyone!

I would just charge it to around 60%. The important thing is that the cells are balanced and the charge rate is about 60%. You'll achieve this the easiest way by charging it to about 60%.

Normal procedure with LiPo batteries.

Thanks, would that be to about when the 3rd light starts to blink?

Just did a quick test.  As soon as the third light started to blink, I disconnected the battery and checked in on the App, it reads 54% charged and all cells are equal. I will use this as my rule of thumb to stop charging before I store them for a few weeks.  

Storage levels 30% 50% for extended periods a 100% charged battery will take about two days approx to automaticaliy discharge to 50% 65%.You can set auto discharge threshold levels within the DJI GO app to save manual discharging