English to Spanish Bus/Financial Accounting Oracle General Ledger Manual

I know that the translation that'll probably pop into your mind will be "el periodo más temprano", but it just doesn't sound right to me. Here's the context:

Original sentence:

The "Period" you enter the first time you translate actual balances will be the earliest period for which you can translate actual balances for any subsequent translations.

Mi intento en castellano:


El "Period" que ingresas la primera vez que conviertes los balances reales será el periodo más temprano para el cual puedes convertir balances reales para cualquier conversión posterior.

Any help would be greatly appreciated.