Why at all a long timeout? Short should be enough.
Just to to give some time for positioners.
But that solution requires users to edit each single channel that is not tuning by hand. Really..?
In any case most users are downloading the channels lists from web, so you'll need to tweak channel lists only once and upload working ones.
Anyway, had a another look my code and I've offloaded the 'auto' parameter problem to SAT>IP servers by ignoring matching key-value pairs from URL. Now, there must a be bug somewhere as the plts parameter appear in the URL although no N is defined on the channels.conf entry.