Chart updating question and multiple units question

Getting closer to having my boat back on the water, has been laid up for a couple of years....long story, not the point here.

Just realized my HotMaps Platinum East card expired in Fall of 2015. I guess I just wasn't aware that the updates are only good for a year and then you have to get a new card, is that right? Any compelling reasons to get a new one now, or just use the old one?

I have a carbon 9 and a HDS9 Gen 3, I'm a little confused if the charting card can be put into one of them but share the charts to both? Admittedly, I need to do some more reading on it. One came with Lake Insight so I had thought about using the HotMaps Platinum in one graph and the Lake Pro card in the other but that seems like it could be a pain. They will be on a NMEA-2000 network, once I get that part all back together.....

Thanks for any help and understanding.