I thought you had up to six months and still opt for redundancy? I too would be interested if you could only test it for one month.
The people in Nera were very vague too about what consitutes "reasonable" commute, and it is the redundancy section who makes these decisions on a case by case basis.
Realistically, how long extra would it take you to commute the extra 16k. In the case examined in the article, because the person was already commuting an hour and the extra 10 miles was going to give them an extra 15 minutes, it did not look as if they might get it.
Also look in your contract for a "mobility" clause.