Since you already have a payroll subscription, you can use an upgraded version you purchase that doesn't include payroll. The subscription will continue even as you upgrade.
As an accounting firm, you might be interested in both the Enhanced Payroll for Accountants, which lets you use payroll in 50 company files instead of 3, and also in becoming a Pro Advisor, which isn't difficult at all (it takes some work to become certified, but that's not required last I checked.) There's an $800 or so fee per year for being a Pro Advisor, but you get both QB Enterprise and Premier for the fee each year, and they don't require renewal after a year (I think even for QB 2022.) You also get a QB Online company subscription, I think, and also discounts on some other software and services.
