A few weeks ago I attempted to profile the Yaffa/Page Publications Marvel editions. The aim was to provide a guide to dating the issues based on the changing formats and cover prices. In doing so I also outlined some of the problems encountered and provided examples of anomalies to my schema.
One of the significant patterns to emerge was that the $0.75 cover price digest issues were all recycled editions of previously published Yaffa editions. These were unnumbered issues and were often retitled.
I have come across just one issue which bucks this trend:
The Incredible Hulk #10 has a $0.75 cover price. It is a reprint of The Incredible Hulk #6. I don't have a copy myself but it does appear to be digest-sized, not regular/magazine-sized.
Generally Yaffa ended their series with a numbered regular/magazine-sized reprint of the first issue in the series. So this issue is anomalous for being digest-sized and $0.75, and for recycling a mid-term issue rather than a first or early issue to formally end the series.
As I say, I don't have a copy to check, but I'm pretty sure this was published early/mid-1982, probably April/May 1982, and may in fact be the first of the $0.75 digests - a transitional issue before the fully-fledged unnumbered/retitled format was settled upon for the final stage. And I don't think there was a regular/magazine-sized #11/$1.10 issue reprinting #1. All supposition on my part - TBC.