To give everyone an idea of how big this is, I don't remember the last time Hamas deployed forward and seized terrain. Currently they holder several towns. Some idiot Irish parliamentarian said Hamas didn't have an airport...but I'm pretty sure you can't paraglide 20 miles into the interior without starting on top of a mountain. So...they were in the a bird at some type of altitude?
Ofakim is 20 miles from the armistice line. Magen, the other town that is inland and not abutting the fence is about 5.5k from an Palestinian town that abuts the armistice line. But the amount of land controlled right now as a percentage is likely very significant.