Hi Wolfgang. I need some more time to come to a conclusion on re-using guiding calibration. I tried several short image runs on different targets approaching the meridian and yes guiding did not recalibrate however this didn't entirely fix the problem. The drift graphics on the guiding TAB indicate it takes a minute or two to get the drift back to pre flip low levels but there is no time delay and the next capture after flip shows drift in the image but subsequent images are OK.
To add complications I am trying to work out why focussing on filter change and post flip doesn't always happen. Same with alignment not happening after flip. I think it depends if or how I have aligned and auto focussed before starting the sequence queue. If auto focus and alignment happens after the flip then it seems guiding has had time to settle down before capturing the next image. Weird because guiding is suspended during these operations.