PR54-11 Eth-to-I2C bridge I2C speed / blocked MUX

we are using your LAN to I2C with 8x MUX board PR54-11 in our labs and production testers and have two questions about:

Q: is there an API command available to change the I2C clock speed „on-the-fly“?
e.g. for a dedicated device we’d like to communicate with 400kHz whereas others have only 100kHz capabilities which must be met. I know that there is an EEPROM stored speed parameter but we need a dynamic change here. A change-reboot sequence is not an option.

We got stucked I2C MUX if one bus that is activated has a blocking device on.
Q: is there a means to reset the I2C Bus-MUX IC if it got stuck?
e.g. if a channel has locked DAT or CLK, a further switch is not possible and all busses are useless.

Any response welcome,