Actually it does matter and you cannot collapse the two groups. There are three levels of membership you need to maintain on this board:
Members (not 501st)
501st Members : belong to 501st, but do not have a Legion approved TD
Sandtroopers : belong to the 501st AND have a Legion approved TD
The last group is the actual detachment members who are eligible to vote in detachment only matters and can see things like election discussions.
This is how it works on CTN, BSN, FISD, etc. as well. You can rename the groups, but you need to keep the three separate. This is spelled out in the charter. can rename them as you like, but they are not the same and need to remain that way.
Welcome to being a DL Noel
And why yes, I did set up the board and this is why it was done that way ;-)