Worth to get SSB (500$) for DBS Multiplier to clock an extra 0.15% via CDP payout?

Not sure if I got it right, but the trick is to purchase SSB for 6 month straight, on the 7th month, purchase another, but I will also get payout, so this is the first month I will get 0.15% extra.

Is this worth if I'm intending to invest the minimum (500$)?