Lien filing deadline

Your last day of work, it seems to me, was probably one of the later dates, but that all depends on what you were doing on that day.

R.C. 1311.02 states that "every person who performs work or labor upon or furnishes material in furtherance of any improvement undertaken by virtue of a contract" has a right to file a lien. So the question becomes, were you performing work or labor, or furnishing material "in furtherance of" an improvement. 

I would argue that cleanup is no furthering the improvement, but work and supplying materials definitely are, so long as those materials are in furtherance of the improvement and the materials are not a broom or mop. 

Basically I always tell people to be ready to defend the last day of work and provide solid evidence of the work performed, or materials supplied, and how that work or materials relates to the project.

If you have any doubt about the work preformed, I would stick to your earlier date, and get that lien recorded next week by hand delivering it to the recorder. The 75 day timeline provided by levelset is correct as long as this is not a residential project. Residential projects have a 60 day timeline.