If your goal was to convert a video file named something like gvh350.mkv with English subtitles, and you saw a timestamp 020457 (2h 04m 57s), here is the real solution.

Users create these long descriptive names for:

HandBrake (GUI)

FFmpeg (command line)
Convert to MP4 with soft subtitles:

ffmpeg -i input.mkv -c:v libx264 -c:a aac -c:s mov_text output.mp4