Hey don't worry. I don't think this method is 100% correct. You are right we can hold steem/sbd for spud4steem. One thing that matters in club5050 is your powerup in last 30 days should be greater than cashout.

And if we talk about SCA, then powerup should atleast be greater than 150.

Your cashout in last 30 days: 252 << 408, Your powerup in last 30 days >> 150 (Min req amount).

So as per my understandings, you are 100% Eligible for club5050 and for SCA tasks too.