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Ah, PP, at least I had the wit to suspect Standard Conditions [see the OP] ! But my solicitor has a track record for saying that she can't do something because it's not the firm's practice or isn't legal when a) it should be, but the firm's practice benefits the firm and not the client and b) it is perfectly legal, and always has been (but not doing it benefits the firm, if only because it avoids the risk of their being in trouble).Big firms like hers do have an eye for their interests, and the juniors, senior associates and even some partners live a life of looking over their shoulder, in case the top partners complain.
She should have given me chapter and verse at the outset, when I first asked for the contractual term