The stake. Sooner or later somebody wants the form changed — a wording tweak, a column, a note above the signature block. The interesting question is not whether you can change it. It is what happens to your change at the next upgrade, and that is a question most teams only ask after an upgrade has answered it for them.

The mental model. The shipped templates are locked, so an upgrade never overwrites them. You duplicate one and edit the copy: the duplicate is yours, unlocked, and can be made your default. Read the lock as protection rather than restriction — it is what makes it safe for us to keep improving the original, and safe for you to keep your version.

Where to look. The Print with Template… action sits in the record's Actions menu. Where a document type has more than one template it lets you choose between them and, if you want, remember your choice for next time. The customer invoice is the obvious case of a record with more than one form available. The guides do not enumerate which templates attach to which document type, so treat that as the pattern to expect rather than a documented list, and let the action itself tell you what is available on the record in front of you.

The worked example. A house-style change to the tax invoice, in three moves.

1. Duplicate the shipped FTA Tax Invoice. The copy is unlocked and belongs to you.
2. Edit the copy — your wording, your layout. The original stays exactly as shipped, so nothing you do here can be lost at upgrade and nothing you do here can break the form other people rely on.
3. Make the copy your default, then print one invoice with Print with Template… to confirm that the record now offers both and that yours is the one that comes up.

The failure mode. Two of them, and the second is quieter. The first: somebody tries to edit the shipped template directly, finds it locked, and concludes the pack is inflexible — the fix is the duplicate, and it takes a minute. The second: somebody duplicates, edits, admires the result, and never makes it the default, so half the office keeps printing the original and nobody can work out why two versions of the same invoice are circulating. Make the copy the default, or use Print with Template… and remember the choice. And if a template you know exists is not offered at all, that is Lesson 1 again: activate it.

The idea to carry forward: the copy is yours and survives every upgrade; the original is ours and cannot be broken by either of us.