I think the "Biden and/or Harris will resign soon" is nonsense, designed to get the right to become lazy (which they are good at) and not work that hard in the 2022 midterms.

With a vacancy at either post, the Dems lose the Senate majority since they no longer have the VP to break a tie. Think McConnell is going to just give the Senate back to the Dems? I don't think so.

If there is a vacancy after mid-year, I think the GOP will delay the VP vote until after the midterms when they have a lot more leverage.

If prior to mid-year, it is hard to see them delaying the VP vote by more than a few months.

I think the solution therefore will be a VP that blocks the Dems from controlling the Senate: in other words, a Democrat Senator from a state with a Republican governor to appoint a replacement (or not appoint one) until the next general election. Tim Kaine of Virginia fits that bill. Of course, the GOP would have to extract a promise that he wouldn't run for president in the future since an incumbent VP has a huge advantage.

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