I am facing a similar issue. The "park from" position is correctly computed by the driver (ap experimental) but ekos reports another position.

The last ppa version from today did not improve the situation. The position in ekos is still not matching the park position coming from the driver but now, it changes at each connection/disconnection of the mount.
the mount is parked on P2, the driver is set to "Unpark from P2"
log at connection:
2018-05-08T19:27:34: [INFO] Site location updated to Lat 48:00:00 - Long 6:00:00
2018-05-08T19:27:34: [INFO] Mount is unparked.
2018-05-08T19:27:34: [INFO] calcParkPosition: parkPos=2 parkAlt=0.000000 parkAz=90.000000
2018-05-08T19:27:34: [INFO] Computing PARK2 position...
2018-05-08T19:27:34: [INFO] Mount is initialized.

Ekos reports: Az:143:07:14 Alt:35:46:52
disconnect then connect the mount

2018-05-08T19:30:57: [INFO] Site location updated to Lat 48:00:00 - Long 6:00:00
2018-05-08T19:30:57: [INFO] Mount is unparked.
2018-05-08T19:30:57: [INFO] calcParkPosition: parkPos=2 parkAlt=0.000000 parkAz=90.000000
2018-05-08T19:30:57: [INFO] Computing PARK2 position...
2018-05-08T19:30:57: [INFO] Mount is initialized.
2018-05-08T19:30:57: [INFO] Time updated.

Ekos.: Az:270:22:50 Alt:00:00:52
disconnect / reconnect would restart at Az:140...

I did several test with other park position, same result.

thanks
Emmanuel

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