Thanks for the reply. It's a long story but an aluminium frame I've ordered has been delivered to me without some of the necessary disc brake cable mounting hardware.
Their solution is for them to take it back, strip it, weld on the correct fittings, repaint it and return it.
I expressed concerns around welding aluminum weakening it (which is what the heat treating process is meant to rectify) but they've come back to say my only option is to return it for reworking without attempting to allay my concerns around how this might affect the integrity of the product. I heard that a second heat treating of a frame wasn't possible. You're overworking the material. But I might be misinformed.
I've been blunt and said I expect a new frame (what I ordered) not a reworked "second" or a refund. I probably wouldn't have taken such a stance if they'd attempted to answer my question in the first place.
Just wondered if anyone knew more about the materials science.