the "elephant in the room" is why a buckboost and not a buck....or rather , interleaved buck as above said
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I presume it is a 4 switch buckboost or three switch…..so anyway you get 2 diodes with reverse recovery in them instead of just one with a buck.
However, The reason to do buck boost would be that sometimes your vin goes below your vout, say
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here is a buckboost sim in ltspice, you can see the voltages..put some stray L in to see the overvoltage ringing. BTW you can put sync fets in in place of the diodes if you wish...or use an LT8705 which facilitates this.