In the 1062.org system the discussion is ended when the appropriate number of members enter their "end discussion" notice. The number of members that trigger that event is determined by the members collectively. By the time the discussion has ended, a certain number of propositions would have been formally submitted.
All members have equal access to participate in each issue, so there is no need to delay the initial process due to late commers. However, provisions have been made to allow for surprises. If the members collectively determine that a decision on the issue is premature (for whatever reason), they have the option to either temporarily deregister from the issue or simply not vote on the issue. If there is an insufficient number of participating members (issue participant minimum) and/or an insufficient number of voting members (issue voter minimim), the issue will be returned to the discussion phase.