Yes, that is true. We could maybe use 50 cards but I probably won’t make it right the first time and then I have 50 cards to recycle.
I used the board file to make some shields but this is something another level. I will have a look around at the University for some expertise in the matter.
Maybe it is simpler for us to use something like a feather board and build from that. But the Mayfly is very convenient for our needs. I have used the Sodaq Mbili as well but had more trouble with that and I’m missing the stackable pin headers.
To bad it is so difficult to order boards from the US. I ordered one of the 0.4 boards years ago and it has been very handy.
Thanks for your input @neilh !