Someone ask here some time ago, if these ballasts may operate remotely.
On the top left is the ignitor, what limit the distance between the lamp and ballast.
It is the simplest form of the superimposed ignitor without any intelligence (the lamp protection intelligence is in the supply part), so if the ballast has to be operated remotely, the ignitor should be deactivated.
Then another superimposed ignitor should be placed close to the lamp (as it is small, it is frequently not a big issue)
Then the cable between this ballast and lamp may be virtually any length.
The advanced functionality (like hot restart timing,...) will stay, as these are part of the supply circuit, the ignitor (even the original one) is used solely to generate high voltage ignition pulses.