Quick answer
By design. AllDone reads the reports you export rather than connecting to the client's ledger. That gives one process that works for every client whatever software they use, and it keeps you in control of exactly what leaves the client's records.
What this means in practice
Going in. You export the trial balance, general ledger, profit and loss and balance sheet, and drop them into the slots. That is the whole connection. A client who moves from one package to another changes nothing about how their job runs, and a client on a package nobody has heard of is not a problem.
Coming out. AllDone never writes to the client's ledger. It produces the year-end journals, and the credit notes, invoices and bills where an adjustment has to touch a customer or supplier balance, in the import layout each package expects. You import them, or you correct the source transactions instead.
Why it is not just a missing feature
Three practical consequences fall out of working from exports:
Nothing is taken that you did not choose to send. The scope of what AllDone sees is the set of reports you exported, not everything in the ledger.
Nothing breaks when a package changes. There is no connection to be revoked, re-authorised or deprecated part way through a job.
One way of working. The same steps, the same slots and the same checks for every client, rather than a good path for the two packages with a connector and a worse one for everybody else.
The only external system AllDone reads from at all is Companies House, for company details, officers and deadlines. Nothing about your client is sent there.
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