Every other week backup to different destinations

I have spoken to support and they essentially said the above was not possible, and instead assign each external drive the same drive letter. However I cannot get Server 2008 to always assign the same letter.

I'm very surprised this isn't able to be accomplished by the built in scheduler and I can't imagine I'm the first one who wants to do this.

Two options:
Use a batch file calling diskpart to always make sure the drives are assigned the same letter. I have something similar in place and could send you a copy if you want. However, diskpart is kinda funky and I am not sure I like this solution.

OR

Create 2 different backup jobs. Each would run every 2 weeks on Thursday, but one would have the effective date set to the first occurring thursday and the 2nd would have an effective date set to the 2nd thursday. I am running 11.5 and do have Effective Date options for weekly backups...