I am 21yo. Is it wise to open scb online trading account now although I'm currently using ibkr? SCB having promo (1june-30sep) on FREE brokerage fees (rebate) on all "Buy" trades. Have war chest $40k aside. Any advice?

Have jumpstart a/c so it's easy to apply online for a trading a/c. Personally am inclined to change due to my fixed structure fees on ibkr that's quite a lot, sadly didn't do my research properly(invested a small sum only, $2.5k, and opened just 2mths ago). If I sell all, returns are good at +8.52%($213). I'll probably invest $2k per mth for Aug and Sep then dca a small amt after, as I'm still an undergrad so maintaining a large dca per mth could be undesirable. PLEASE ADVISE ON FEES LONG RUN.