Tried and tested this myself, have gotten few thousands worth of SocialGood coins and cashed out to USDT.
IMO eBay AU works best with tracking(12-24 hours) and approvals always happen at the end of the following month, so it takes 31-60 days for eBay AU.
Aliexpress have also worked for me. Haven't really tried other stores.
New users need to spend US$30 or more within 30 days of signing up.
According to SG rep, increased referral expires 24/12/2021 midnight JST.
For those who have more questions about the SG/App, withdrawals, feel free to DM me, happy to help answer any questions. I've been using the SG app for about 7 months now.