In Admin > Setup > Accrual Plans, you may specify rates of accrual depending on length of tenure with the company. The "Months of Service" column on the Schedule tab means months of completed service.  For example, if you allow people to accrue 10 hours per month for their first year and 13.333 hours per month for their second year, you would populate "Months of Service" with 0 for the first row and 12 for the second row.  

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