We checked, there is no wor around to avoid the 0x07 output while using UART since it is Async transmition mode.
The only work around is resend the read command when you receive 0x07 response. it should successful in second try.
Also you can try to upgrade our BNO055 FW to 03.14 or higher version. Then you will have INT_STA which is the data ready interrupt. With this interrupt, you will know the fusion calculaiton is done. then you submit read command, it should not meet overrun error.
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