The same buttons are used for skipping forward & back in recordings or whilst you’re watching.
The left-hand (curly arrow) is the instant replay
Recording > Instant Replay
The right hand (arrow with vertical bar) is the skip forward
Recording > Skip Forward
So with skip forward set to 1 minute, 4 presses jumps you quickly through a 4 minute advert break
If you’ve skipped too far, Instant replay (set to 15 secs) will jump you back a bit,
So if the ad-break was actually 3 1/2 minutes 4 presses forward & 2 presses back take you to the next section of the program.