Bridges in sys-whonix: are they rotated, or one is used and the remaining are for backup?

Are OBFS4 bridges used in sys-whonix rotated, or only the first one in the list is used generally the one used and the others are there just in case the first isn’t working?

If rotation is in place (as it should be), are there any specifications available? or it’s knowledge restricted to Tor developers?

I’m not using tor provided-bridges, I’m providing my own in the sys-whonix connection wizard…

If anyone knows which log file in sys-whonix I can check to see which bridge is being used, please let me know…

All that Tor Control Panel or Anon Connection Wizard - Whonix is doing is writing a configuration file. Once that is done, no further changes are made to Tor configuration by these tools. The user can review the written configuration on the disk.

On configuring Tor in Whonix:

How Tor chooses to use or not use bridges is unspecific to Whonix. Same as upstream Tor by its original developers, The Tor Project.

related:
Tor Routing Algorithm

Can be resolved as per: