I have also done some research on this matter.
First, I haven't seen any domestically published versions.
Secondly, I had a similar entity in my mind (and was able to estimate its characteristics and successfully identify the five digits of BH8's call sign). However, I didn't intend to document this. Because the calculation method might not be precise, and the estimation doesn't have much practical value. For example, if we take the 8th district in Chongqing as an example, it started announcing the cancellation of the first batch of numbers that had been removed from the list around mid-last year [for the first time]. However, it is still unknown how long it will take before these numbers are re-released.
Finally, from the perspective of "wind direction," some call signs belonging to "older amateur radio enthusiasts" should not be relinquished under any circumstances, as there are precedents for this.
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