From RHESSI Wiki
Passes are defined as times when RHESSI is in contact with a ground station. This occurs about 6 times a day due to RHESSIs orbit. The pass times appear to shift forward approx. 6 minutes every day. Then every 3 days a new pass can be seen which effectively shifts the passes back by 1.5 hrs. Check these numbers in a couple of years.
Pass times can be found here. Subtract 8 hours from AOS to get the local time.