WCG work units have a much shorter deadline (I think like 10 days) so being offline for a month will not work. If you can manage to connect about 1 time per week you should be OK if you set the "Connect about every X days" and the "Additional work buffer X days" settings in your preferences to make X be the amount of time between your opportunities to connect to the internet. I would not suggest the 10 day max beause if anything goes wrong you may not return the results in time and then your crunching efforts would be lost.