Well, it seems that Trek can’t source a replacement frame for my bike, so… they’ve offered to replace the whole bike with a new one, an L600 (as opposed to the L500 I had). I agreed to it even though it’s a hard-tail bike as there were no other real options available. Trek don’t do rear suspension bikes anymore.. maybe they found that they couldn’t design them correctly?
Anyway, they’re still going to have to source the replacement bike from the Netherlands (as Trek UK don’t sell hub geared bikes) so it will take a few weeks for the replacement to arrive.
Now, all I have to do is see if I can get the rear wheel rim on my old bike replaced as a same-day service in a bike shop near work before it collapses on me.