OK, Well I upgraded to 4.3 today. I didn't see your message until now so I didn't backup the .hts directory. I guess there's no going back now. :P
I had an issue where some of my channel icons were overwritten because Configuration->Channel/EPG->EPG Grabber->General settings: Update Channel Icon: was checked. When I unchecked it and refreshed the icons, the paths were restored correctly but after clearing the PVR database in Kodi, no icons at all were displayed.
I got to the bottom of it after reading this post, which has the fix: https://forum.libreelec.tv/thread/1253-libreelec-tvheadend-local-kodi-fetching-picons-very-slowly-and-with-curl-timeout/?postID=86589#post86589
Anyway, I digress. I tried both "$q$n.$x" and "$t/$t-%Y%m%d-%H%M$-c.$x" as suggested, without much success. Both resulted in the intended file naming structure alright, they just didn't scrape into the TV Shows library.
In the end, I read the documentation and came up with "$t/$t $c %F %R $e.$x" Which works very well for me. :)
It's shorthand for "ProgramTitle/ProgramTitle ChannelName ISODate 24hrTime EpisodeInfo.FileExtension" The directory/filename produced will look something like this:"Kirstie and Phil's Love It or List It/Kirstie and Phil's Love It or List It More4 2018-10-09 16-55 S03E03.ts" Note I used spaces as delimiters. It might not be necessary to include the channel name as you say, or date and time info, but it seems to work OK, so I'm leaving it for now. Some clients might not like space delimiters so you may need to use _ or something else if this is an issue.
So in summary:
There's probably no need to upgrade to the development version of TVH (Though it's fairly straightforward to do).
In Configuration->Recording, under Filesystem Settings:Format string/Pathname specification: put "$t/$t $c %F %R $e.$x" (without quotes) into the textbox. The resulting filenames should then scrape into the TV Shows library.