Disrupted Study Period, Qualifying for ARC

I manage a business which is not based in Taiwan and have been living in Taipei for the past 18 months, making visa runs to reset my 90 day multiple entry. In my case, I don’t require an ARC as my current setup works satisfactorily, however, the state-covered healthcare would still be a plus. I’m considering the ARC-through-study route and have the following question: I was enrolled for a semester at the Mandarin Training Center over a year ago, but have since not continued classes. In order to acquire an ARC, which I understand one may apply for after 4 months of residence and study with proof of ongoing enrollment, will it be necessary to restart classes full time for another 4 months first before applying, or would my earlier class at the MTC still count towards the 4 months required? I think it’s doubtful, however any clarification would be appreciated. Thank you.