GM Kevin Spraggett (January 2012, email correspondence): 'Canada decided (around 1995, I think) that since FIDE was undecided about when to resume its own interzonals, to hold regular zonal championships. But as FIDE did not quickly resolve the issue, a number of 'backed-up' zonal champions were put on a hold list. I participated in the 1997 Groningen World Championship because I won the 1994 Zonal. And I played in  Las Vegas for winning the 1996 Zonal.
In the aftermath of the 1993 scandal of Kasparov and Short leaving FIDE and setting up their own world championship system, the CFC [Chess Federation of Canada] had no idea that it would take so long for FIDE to sort things out. It is ridiculous to simply become paralyzed and stop organizing interzonals or their substitute. We only assumed that it would be off by a cycle...instead it was several cycles and when it did return it was never the same format. At one point I offered to 'surrender' one of my backed up zonal titles -- to allow another zonal championship, but the CFC rejected it.'
I updated my index page, World Chess Championship Zonals, to include this information. I'm not aware that the cancellation of the 1996 Interzonal, which was the action that caused the problems for the CFC, has been documented anywhere. It's not mentioned on Wikipedia's FIDE World Chess Championship 1998, and would be a suitable subject for a future post.