Venue transfer diagrams:

The venue transfer state machine on the venue requesting the transfer:

stateDiagram-v2
[*] --> Requested
Requested -->Accepted: Accept by the requesting venue
Requested -->Rejected: Rejected by the requesting venue
Accepted --> Rejected: Rejected by the requesting venue
Accepted -->In_preparation: In preparation by the receiving venue
In_preparation -->Rejected: Reject by the receiving venue
In_preparation -->Sent: Sent by the receiving venue
Requested -->Cancelled: Cancel by the requesting venue
Accepted -->Cancelled: Cancel by the requesting venue

The venue transfer state machine on the venue receiving the transfer:

stateDiagram-v2
[*] --> Not_sent: Purchase order created in the requesting venue
Not_sent -->Requested: Sent to the requested venue
Requested -->Accepted: Accepted by the requested venue
Requested --> Rejected: Immediately rejected by the requested venue
Accepted --> Rejected: Rejected by the requested venue
Accepted -->In_preparation: In preparation by the requested venue
In_preparation -->Rejected: Rejected by the venue being requested
In_preparation -->Transfer_out: Sent to the requesting venue
Requested --> Cancelled: The requesting venue cancelled the transfer
Accepted --> Cancelled: The requesting venue cancelled the transfer
Transfer_out --> Invoice_created: Converted to Invoice in venue that requested the transfer
Not_sent --> Cancelled: The requesting venue cancelled the transfer

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