When you create the company you are asked for the 24 accounting periods you want to start entering transactions, those dates must start in 2020. If your starting transactions are 1/1/2020 then that accounting period must be open in Sage. When your done entering 2020 and 2021 data you would close the 2020 year to continue to enter transaction in 2022. Rather than enter 3 years of data you could just enter beginning balances for A/P, A/R, and any other inventory, jobs and bank recon as of 12/31/2022, then start entering actual transactions starting 1/1/2023

Thank you, this resolved my misunderstanding of that prompt during company creation.

We have done a number of QBO to Sage50 conversions for clients and have tools that can get that history into Sage without any manual entries.  Reach out directly if you want me to take a look, if we can't get the data to migrate we wouldn't charge anything so there is no risk to you.  [email protected]