No No & Thrice No. But, it is fair to say the U23s mainly start with a back 3 & wingbacks. The U18s rarely to never. The U18s are nearly always a conventional four. Because it is Development football there are many, many more in game positional & tactical changes than in first team football. Because player development matters more than game result. There are great stories of Academy teams (more generally, not necessarily ours) being drilled all week as a Three, sent out as a three, but switched to a four after 15 minutes, with no warning & no reason. There's a story that Ajax sent out with their strikers in defence & their defence as strikers. Taking players out of their comfort zone is a great route to development.
But, fair play, yes, the U23 part of the Academy will more often than not set up as a three. With Ange either at LWB or up top.
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