My understanding is that the first time anyone actually measured the ozone concentration in the Antarctic atmosphere during winter was the early 1980's. My guess is the ozone hole has been around for a lot longer than the 1980's.
Correct, there could be a cycle of ozone holes that is related to solar cycles, one could only tell if you wait for several solar cycles to pass.
There is also the problem that people think of this a science anyway as it is an open system where there are any number of uncontrolled variables. It is a theory that arrived at just about the same time as some patents expired. The original theory was based on methane – the biggest source of which is termite mounds in the rain forest.
Non of this means that it is or isn't true – but no one really has a clue as to what the truth is here.
The ozone hole was first discovered due to ground-based measurements made by the British Antarctic Survey at Halley Bay, Antarctica; the measurements commenced in the 1950s. The decline in ozone was noted first here; instrumental observations from satellites had been corrected because the occurrence of the hole was first thought to be an instrumental anomaly.
The figure below shows the record of ozone measurements in October at Halley Bay.
