You insert all of them in the order you wrote them down - assuming that is the same as the order they were shown to you by the wallet when you wrote them down.
Step 1 - Launch Trust Wallet
Open Trust Wallet and then tap on Settings.
Step 2 - Access Wallets
In the Settings screen, ...
How likely is it that some block from 1 year ago later turns out to be invalid?
Very unlikely, but I think that isn't the problem.
The problem is, how does a new user find out the current state (UTXO set or equivalent) without having to trust other parties? Any community has dishonest people preying on it.
You cannot ignore, expire or invalidate unspent ...