Different plans for different joins orders

opportunitylink__c->
	[Opportunity__r->Linked_Reseller__r,
	contract__r->Account]
	 AND
	replacementcontract__c->Contract

select c.contractnumber
from salesforce.opportunity o
    left outer join salesforce.opportunitylink__c ol on o.id = ol.opportunity__c
    left outer join salesforce.contract c on ol.contract__c = c.id
    left outer join salesforce.account a on c.accountid = a.id
    left outer join salesforce.replacementcontract__c rc on c.id = rc.replacedbycontract__c
    left outer join salesforce.account lra on o.linked_reseller__c = lra.id
where o.type = 'Maintenance'
    and o.id IS NOT NULL
    and ol.opportunity__c IS NOT NULL
    and ol.contract__c IS NOT NULL
    and c.id IS NOT NULL
    and c.accountid IS NOT NULL
    and a.id IS NOT NULL
    and a.exclude_from_corporate_stats__c = false
    and lra.exclude_from_corporate_stats__c = false
limit 100;

OPTIMIZATION COMPLETE:
PROCESSOR PLAN:
ProjectNode(0) output=[c.ContractNumber] [c.ContractNumber]
  LimitNode(1) output=[c.ContractNumber] limit 100
    JoinNode(2) [ENHANCED SORT JOIN (SORT/SORT)] [INNER JOIN] criteria=[o.Linked_Reseller__c=lra.Id] output=[c.ContractNumber]
      JoinNode(3) [ENHANCED SORT JOIN (SORT/SORT)] [LEFT OUTER JOIN] criteria=[c.Id=rc.ReplacedByContract__c] output=[o.Linked_Reseller__c, c.ContractNumber]
        AccessNode(4) output=[c.Id, o.Linked_Reseller__c, c.ContractNumber] SELECT g_2.Id, g_0.Linked_Reseller__c, g_2.ContractNumber FROM ((salesforce.Opportunity AS g_0 INNER JOIN salesforce.OpportunityLink__c AS g_1 ON g_0.Id = g_1.Opportunity__c) INNER JOIN salesforce.Contract AS g_2 ON g_1.Contract__c = g_2.Id) INNER JOIN salesforce.Account AS g_3 ON g_2.AccountId = g_3.Id WHERE (g_0.Type = 'Maintenance') AND (g_0.Id IS NOT NULL) AND (g_1.Opportunity__c IS NOT NULL) AND (g_1.Contract__c IS NOT NULL) AND (g_2.Id IS NOT NULL) AND (g_2.AccountId IS NOT NULL) AND (g_3.Id IS NOT NULL) AND (g_3.Exclude_from_Corporate_Stats__c = FALSE)
        AccessNode(5) output=[rc.ReplacedByContract__c] SELECT g_0.ReplacedByContract__c FROM salesforce.ReplacementContract__c AS g_0
      AccessNode(6) output=[lra.Id] SELECT g_0.Id FROM salesforce.Account AS g_0 WHERE g_0.Exclude_from_Corporate_Stats__c = FALSE

select c.contractnumber
from salesforce.opportunity o
    left outer join salesforce.opportunitylink__c ol on o.id = ol.opportunity__c
    left outer join salesforce.contract c on ol.contract__c = c.id
    left outer join salesforce.account a on c.accountid = a.id
    left outer join salesforce.account lra on o.linked_reseller__c = lra.id
    left outer join salesforce.replacementcontract__c rc on c.id = rc.replacedbycontract__c
where o.type = 'Maintenance'
    and o.id IS NOT NULL
    and ol.opportunity__c IS NOT NULL
    and ol.contract__c IS NOT NULL
    and c.id IS NOT NULL
    and c.accountid IS NOT NULL
    and a.id IS NOT NULL
    and a.exclude_from_corporate_stats__c = false
    and lra.exclude_from_corporate_stats__c = false
limit 100;

OPTIMIZATION COMPLETE:
PROCESSOR PLAN:
ProjectNode(0) output=[c.ContractNumber] [c.ContractNumber]
  LimitNode(1) output=[c.ContractNumber] limit 100
    JoinNode(2) [Dependent] [ENHANCED SORT JOIN (SORT/SORT)] [LEFT OUTER JOIN] criteria=[c.Id=rc.ReplacedByContract__c] output=[c.ContractNumber]
      AccessNode(3) output=[c.Id, c.ContractNumber] SELECT g_2.Id, g_2.ContractNumber FROM (((salesforce.Opportunity AS g_0 INNER JOIN salesforce.OpportunityLink__c AS g_1 ON g_0.Id = g_1.Opportunity__c) INNER JOIN salesforce.Contract AS g_2 ON g_1.Contract__c = g_2.Id) INNER JOIN salesforce.Account AS g_3 ON g_2.AccountId = g_3.Id) INNER JOIN salesforce.Account AS g_4 ON g_0.Linked_Reseller__c = g_4.Id WHERE (g_0.Type = 'Maintenance') AND (g_0.Id IS NOT NULL) AND (g_1.Opportunity__c IS NOT NULL) AND (g_1.Contract__c IS NOT NULL) AND (g_2.Id IS NOT NULL) AND (g_2.AccountId IS NOT NULL) AND (g_3.Id IS NOT NULL) AND (g_3.Exclude_from_Corporate_Stats__c = FALSE) AND (g_4.Exclude_from_Corporate_Stats__c = FALSE) LIMIT 100
      DependentAccessNode(4) output=[rc.ReplacedByContract__c] SELECT g_0.ReplacedByContract__c FROM salesforce.ReplacementContract__c AS g_0 WHERE g_0.ReplacedByContract__c IN (<dependent values>)

left outer join salesforce.account lra on o.linked_reseller__c = lra.id
    left outer join salesforce.replacementcontract__c rc on c.id = rc.replacedbycontract__c

 left outer join salesforce.replacementcontract__c rc on c.id = rc.replacedbycontract__c
 left outer join salesforce.account lra on o.linked_reseller__c = lra.id