Question for the specialists here (@findegil, Deagol, Berelach) -

I just received a fourth impression of the Houghton Mifflin 1st edition Return of the King, as identified using the Tolkien Collector article in issue #22 by Steven M. Frisby. My copy matches all of the identifying damaged text indicators to make it a fourth impression.

My question is that the publisher records that Deagol provdes at tolkienbooks.net say
As printed, all sheets bore the A&U imprint. In December 1958, 1,000 copies were converted to Houghton Mifflin copies by use of a cancel title.

My copy's title page is fully integral with the rest of the gathering (continuing on to page 13/14). It is not what I would typically consider a cancel title leaf like my 1st impression of the same title, where you can clearly see the stub of the original title leaf that the cancel one has been pasted on.

Is the "cancel title" that Deagol noted incorrect, or not for all 1000 copies, or was the entire sheet in the gathering replaced before binding, or...? Any ideas? Anyone else with this impression to compare against?

Thanks!