If I was you, I'll try the MSI forum's method (you can find it in the previous pages of this forum too)
In short you have to disable TPM from BIOS and restart, before any BIOS update.
Windows should ask for the same weird pin change, but this time you should be fine since you didn't change any
hardware component, TPM settings included.
After doing that, you're free to update BIOS every time you want and without the need of doing again this procedure. At least, accordingly to the before mentioned MSI forum.
You'll ever have to script safe net, if something goes wrong.