BND vs T-bills

When becoming Bogleheads, my wife and I put our bonds into BND just for the simplicity. We haven't taken a look at our accounts recently, but given the good returns I've heard on T-bills, we're thinking of moving our bond (BND) allocation over to T-bills instead. Likely short term.

Is there any benefit right now to holding BND over T-bills? I have read that it effectively is Vanguard's bond ladder so can benefit from both long/short maturities, but the T-bill returns are looking enticing.

Also...do Treasury Bills count towards a Bond allocation? Or a short-term asset (if we get the 30 days)?