Pro Forma, Period Adjustments

Hey guys, few questions here:

1) I'm looking at a company that has decided to change its year-end reporting date from May 31 to December 31. Their latest report is for 7 months, ending in December 2013. How would you guys go about modeling this company out? Would you add the following quarter to it, and compare that entire period to previous fiscal year reports? Or would you take the quarter before this 7 month report, add that, and so on to adjust all previous reports and have it set up for new fiscal reports?

2) Until now, I've been only going by annual reports. Not to say that I haven't been adjusting my forecasts with every quarter/news report, but my models are all annual-based. Do you guys have a specific way you update your models for quarterly reports? Do you have two separate spreadsheets, one quarterly-based the other annual? I think that would help in better understanding the cyclicality of a business, but it seems like your valuation might come out different because of the compounding effect, no?

3 Any general thoughts on how you approach annual vs quarterly valuations, or good resources would be cool.

Thanks.