What does restoring do to work I have done since?

Nothing. Neither restore option deletes anything, and anything created since the snapshot is left exactly as it is.

There are two buttons and they differ only in how much they put back.

Put back N deleted rows re-creates what has gone missing and touches nothing else. This is the one you want after an accidental delete.

Restore everything to this point also sets rows that have changed back to what they held at that moment — so a note you rewrote returns to its earlier wording. Use it when you want the account as it was, not just the missing pieces.

Neither one removes anything. The panel says so under the buttons: "Neither one deletes. Anything created since stays." A trade you logged after the snapshot was taken survives both options. That is a deliberate design decision — a restore that could delete your last three days of trading would be a worse accident than the one you are trying to undo.

Both preview before they act. You always see the counts, per area, before anything is written.