The full fare rules suggest that this fare is completely cancellable/refundable -- you should be able to cancel before departure or even no-show and get a refund, and you should be able to make changes for free.

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Strangely, I see two M fares filed here --one @ $139, one @ $878 (both amounts base fare).



The different is in the routing rules. The $139 base fare is only valid on nonstop travel; the $878 base fare is valid on DLA-JNB-LBV as well.



They both have identical fare rules, which say in part…

In the PENALTIES section:
In the CHANGES section:
Here's a way to find the full fare rules, nicely formatted for human consumption in a way that makes more sense than UA's wall of text, on matrix.itasoftware.com ::
Find the flight:


From the flight details page, click on the "rules" link in the fare construction:


This gives you a nicely formatted bundle of rules; here's a sample:



(My understanding is that this text is an automatically generated translation of rules encoded by a computer program, which is why you get the redundant "cancel before or after departure for a refund" and also the text that has ~no effect, "discounts for children and infants apply" and "penalties waived for upfaring or in case of death or illness".)

One hint that this fare carries on change/cancellation fees is that the text doesn't mention "XAF" anywhere. Usually when fares specify a change or cancellation fee they do it in the local currency (usually the currency of the country of the first segment on the itinerary because that's usually the ticketing city).

If you're uncomfortable buying the ticket from united.com because of the (apparently incorrect) boilerplate text shown before purchase, give a UA reservations agent a call and ask them to walk you the fare rules. They should be able to confirm whether there's anything wonky going on.