Setting aside money for taxes

[Sam Dal]

Folks - got a large commissions check of a few hundred K and my CPA tells me I still don't need any quarterly payments as employer has withheld enough. However, he believes there could be a 80-120k tax due on April 15 depending on what additional commissions I have in 2026. My main question isn't about taxes but how to invest the current funds sitting in my Chase account

1) Invest in FXAIX as I usually do (already maxed out backdoor Roth and post-tax Roth and have sufficient 529). In early April, I figure out which long-term lot to sell and also have some losing shares to balance out capital gains

2) Go conservative and park 120k in Fidelity auto-roll T-bill for 8 months and place the rest in FXAIX

Thanks