There is now a new option "Extended block length test" of the "Make block correlation analysis" button on the Workbench tab.
When a block has been tested, it is successively lengthened with the blockdistance and then again with the blockdistance.
These new blocks are tested for best and next best position within the reference. Result is presented as a sorted "sets sample to year number-list".
Missed or erroneous rings may be discovered with this tool, which is available within the development (test) version!