I charge by the 'stage', unless contracted for 'full service.
If a project requires planning consent then my fee includes initial consultation, feasibility, survey, drawings and completing the planning application.
These are clearly marked 'For Planning Consent Only'
If successful (or planning consent was not required) then I prepare detailed drawings for building regulation approval. The fee also included any negotiations with building control but not structural or other specialist design.
These are clearly marked 'For Building Regulation Approval Only'
Once the client has all the necessary approvals in place then they are free to take the project from then onwards or if they want I can then provide contract drawings, tender documents, administer the contract etc.
Copyright is always vested in me however my clients are free to use my drawings to tender or negotiation, bearing in mind the intent of each stage's drawings.
The whole purpose of copyright is to protect my intellectual property - my design. If a client wants to muck it up with poor construction or various on-site changes then that is up to them. My only stipulation is that they could not exhibit that finished item as representative of my work.
Your architect is morally wrong in attempting to restrict your choice of contractor on the pretext of copyright.