Looks like some milling was omitted on that plane, wouldn't be surprised if it were chattery
with such a distance for the cutter to travel.
Some recent(ish) postings from D_W, he tested a few new planes out and mentioned of some trouble with the lever cap sitting nicely,
causing some issues with the adjuster, or something along the lines of that.
The adjuster too stiff to turn or some other such thing.
Perhaps the turnscrew makes this less noticeable, and the manufacturers can get away
without milling the bed of the plane?
Perhaps some work with a flat needle file might be required, should there be adjustment of
the frog to sort matters...
that is, provided it somewhat bears resemblance to the vintage era,
and by that, I mean the ones made after the solid faced frogs, which I would have guessed
is the pattern most of the cheaper planes were based on.
Should you wish to sort this plane out, a proper inspection of the vintage Stanley's or Record's is worth having in hand, if you ask me.
Plenty of reasons to have more than one hand plane.
All the best, and good luck with yer bidding.
Tom