Deleted Time Phased Data

Wondering if anyone on here is using Time-phased data to do quarterly utilization reports. We have it all set up but then suddenly the data reset to 0. After many emails back and forth with support, I found out that the time-phased data is deleted (not sure frequency yet) and you need to request to keep it (again not sure how long you can keep it for). Apparently it is only stored for 30 days unless you request for it NOT to be deleted. This doesn't support our current design so looking for some advice on how you can do more than 30 days of utilization reporting in Clarizen or do you have to export it out via API. And if you have to export it out - how does that work as we have to look for updated records and then we end up bringing in duplicates if the record is not found. HELP!