After su6,my airliners have problems in following nav plans

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PC version.
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Are you using Developer Mode or made changes in it?

Brief description of the issue:
I first found 787,747 and 320 wont follow the nav plan after the su6. After further tests i found it happened just under certain conditions .
After start up MSFS, it happend(wont follow nav error) if i first take the challenge flight ,howerer If i didnt do any flights but just start a airliner and the error never happens.
Dont know why ? No such error before su6. Everything is default and no addons.
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