Fenix 6 Sapphire: open water swimming accuracy following upgrade to software 23.00

I have not had any problems. Track was recorded as normal.

I have had accuracy issues also on open water swimming since late August.  It is usually off (under) by 600 yards on swims of 2000 to 5000 yards.

I think OWS distance in versions 22 and up, is a combination of GPS distance and stroke length derived from acellerometer data. When I look at my OWS swim data, recorded stroke lengths are either correct, or exactly half what they should be, perhaps because strokes are often missed or double-counted. This depends on the wind, which influences my position in the water and swim style. The distance as determined by stroke length only, is between 50% and 75% of what it should be. This is probably used to 'correct' the GPS data with, and so the distance is shortened. After exporting the GPS data as GPX, the distance will be correct. This has been reported on the beta forum a couple of times. When using software 20.60, stroke length is recorded correctly and the overall distance is also correct. I am a terrible swimmer, quite slow, and below a certain speed the stroke detection in the newest versions may not work optimally. Just guessing here though.

Problem seems to be that the "off" tracks were recorded in multi-sport activity (bike-swim-bike) mode. After I spent quite some time after the first cycling in transition, I press the lap-button and start swimming. It seems the GPS signal is not picked up for swimming and the result is as above (cycling tracks are ok) 

When swimming only, selecting "open water swimming" waiting until GPS bar on top of the watch face is green, then pressing start, the tracks are ok (not sure whether 100% accurate, but at least plausible)

Not really satisfactory and I don't quite understand why when cycling GPS seems to be ok, when swimming not