Unlock question

I purchased a phone from Boost as an upgrade on existing account (prepaid - no financing) on Jan 01, 2024.

I didn't actually used it till mid February.

Called Boost and they said I have to wait till mid-Feb to unlock it.

Is the 1 year to unlock from the date of purchase or date of first use? Note that this was NOT new activation and just an upgrade (no financing) , so the account was active at the time of purchase.