N0xiety Sorry for the delay. Yesterday, I got the detail about the issue. Before, I thought the expire time is 90 days. However, I'm wrong. Our developer told me it's 3 months. 3 months is different from 90 days. What you got in 11/27/2017 will be expired in 2/28/2018 0AM. 11/28/2018, 11/29/2018 and 11/30/2018 will together be expired in 3/1/2018 0AM as there is no 2/29 2/30 2/31 in year 2018.
So let's do a math calculation here. Yesterday, 56 bonus expired for you. It's 11/28 (8+5+5=18) + 11/29(10+5+5=20) +11/30(12+5+5=22) and 4 SS may be consumed. So 56 (18+20+22-4=56) SS expired yesterday according to the calculation. However it only showed the number of the expired old SS. There is another bug just found by us. 1/30(5+5+8=18) which is the new SS is also expired yesterday but the number is not added. So totally it's 56+18=74 SS expired yesterday (It's really a huge amount, I don't know whether you consumed it or not). Can you confirm what I said in you SS list page. Thanks.
Currently, I don't know what to say about the expire settings. But I will try my best to get the detail and explain to you, my dear daoist.