Yeah it will be 3-4-2-1, technically speaking it will be like our 4-2-3-1 with the right players, and I dont mind it due to our lack of RB options.
Gigi
Höwedes - Rugani - Chiellini
Cuadrado - Pjanic, Matuidi - Sandro
Dybala - Mandzukic
Higauin
Is very close to a:
Gigi
Höwedes - Rugani, Chiellini, Sandro
Pjanic - Matuidi
Cuadrado - Dybala - Mandzukic
Higauin
Its basically the same role for most players, main thing that changes is Chiellini will have the freedom to move further up with the ball then usual I'm guessing. The roles for the others should stay fairly similar most likely (for example Mandzu goes central and leaves whole left to Sandro anyways). Höwedes was never likely to join the attack so RCB or RB is not too different for his tasks. Dybala will still operate in the channels (and get lost...), ocassionally drift wide.
The shape or functionality of the above only changes drastically if Cuadrado is not available btw, you cannot play Licht instead of him, then it essentially becomes broken system with 5 defenders, then fluid or mobile as it could be.
Main difference will be there will be NO overlapping behind Cuadrado, that right side CB will stay put, or just receive passes for safety.