Is it more important to keep my job or complete my community service if I can't do both?

I have a job. But due to my deferred felony possession of less then a gram of coke it is hard to keep a job with mandatory hours that needs to be provided by the employee; its hard to do community service. I currently work in construction, mainly tieing rebar 6 days a week. I pay $165.00 a month and my probation needs 40 hrs. of community service out of me by the end of this month but i'm trying to keep this job. I lost jobs due to a company finding out my limited requirements. I spend 2-3 weeks seeking another one if it comes that quick. I also have been sick with a 105.0 fever so its outside service I can do Sundays but I was just re-assigned to this place and barley am able to! I can give at least 20-25 hours before December 31, without losing my job. Whats more important job wise? Or community service wise? Any professional criminal attorney can help ease these questions?