Israel has moved the blocks which are supposed to mark its post-ceasefire line of control deeper into Gaza in several places, sowing confusion among Palestinians.
Satellite images reviewed by BBC Verify show that in at least three areas Israel placed blocks, before returning later and moving the positions further into the Strip.
Under the terms of the US-brokered deal with Hamas, Israel agreed to withdraw troops beyond a line marked in yellow on Israeli military maps, which it has illustrated on the ground with concrete yellow blocks.
Defence Minister Israel Katz warned in October that anyone crossing the Yellow Line would be met with fire.
Since these comments were made, there have been a series of deadly incidents around the line.
In Beit Lahia, Jabalia and al-Tuffah, the Israel Defense Forces (IDF) placed blocks and later returned to move them deeper inside Gaza. In total, 16 positions were moved.
In the al-Tuffah neighbourhood of Gaza City, satellite images show that IDF troops moved at least seven already placed blocks between 27 November and 25 December.
The position of the markers was moved on average 295m (968ft) deeper inside the Strip.
As well as the blocks that have been moved, BBC Verify mapped 205 other markers. More than half of those have been placed significantly deeper inside the Strip than the line marked on maps.
An IDF spokesperson said it rejected all claims that the Yellow Line has been moved or its crossing by IDF troops.
Analysis of satellite images up to 11 January suggests some sections of the Yellow Line - which the head of Israel's military described as a new border line - remain unmarked on the ground more than three months after the ceasefire began.
The latest satellite images reviewed by BBC Verify show that blocks have not been placed along roughly 10km (six miles) of territory, leaving some people in Gaza struggling to know where the beginning of what the IDF calls a dangerous combat zone is.
Recent eyewitness accounts depict a terrifying atmosphere, with one individual stating, We are now living inside the Yellow Line, behind the yellow blocks, with no idea what our fate will be. These developments have raised alarm among human rights experts about the implications for civilians and the risk of escalating violence.















