So I’ve had my Mini since November 2019, never had Care Refresh before.  If I follow the video instructions from DJI and submit in order to purchase package will the Care Refresh last 12 months or just the remaining warranty period?  Second question, am I right that only 2 back to back Care Refresh can be purchased?

You can only buy it twice, the original DJI care refresh and thhe care refresh +, and only if you did not claim the 2 replacements. If you have 2 replacements within the year, then you cannot extend it. So you are only entitled to 2 replacements even if you buy both care refresh. As for the period, I would guess that it is one year even if you are out of warranty, as long as you provide what is needed to buy the care refresh. Since this is an external warranty that cover damage and user error, not things that would be covered under warranty. I hope they respond because I would like to know as well.

Hi there, the DJI Care Refresh is valid for 12 months and offers up to two full replacements at an additional charge if your product is damaged because of accidents or during normal use.
If your DJI Care Refresh has not yet expired, and there is at least one product replacement left, then you can purchase DJI Care Refresh +. Each product is eligible only once for DJI Care Refresh and DJI Care Refresh +.