It may depend on what you own. If you own a timeshare where you maintain your own Interval International membership, then do as noted above. Just don't tell them. II doesn't care and as long as you keep paying your annual membership fee you can keep booking getaways.
If you own in a system like Marriott, Vistana or Hyatt where they pay for your II membership fee through your Club Dues fee, then they will automatically close out your II account.