address for tax payments

The form instructions say where to mail checks. Presumably the software is following the directions.

Refer to Page 114 of Form 1040 instructions  available at IRS.gov

Periodically the IRS changes the addresses based on work flow/staff availability.

One year, Virginia payments had to go to Fresno.  That seemed silly but just follow the directions and things should work out fine.

Congress likes to fool stupid taxpayers into thinking they are cutting back IRS employment (and therefore the number of clerks who carry guns) by contracting out the work of opening envelopes and cashing checks to "private lockboxes" -- i.e., banks that bid on this work.  From time to time they get a better price by switching where the work is done.  

Once the check is cashed in Cincinnati (probably, across the river in Kentucky, but that's another story), the return will be shipped to Ogden, likely just down I-84 from your client.  And that's today's lesson in government efficiency.  

And, of course, this has nothing to do with the fact that Kentucky has two Republican senators and California has two Democratic senators.