Somehow you manged to end up endup with Ruleset schedules with no default Day schedules. The bugious schedules are:

OS:Schedule:Ruleset,
  {c648dc32-56ca-4a1e-9af5-501442111cf8}, !- Handle
  25C Office no setback,                  !- Name
  ,                                       !- Schedule Type Limits Name
  ,                                       !- Default Day Schedule Name
  ,                                       !- Summer Design Day Schedule Name
  ;                                       !- Winter Design Day Schedule Name

OS:Schedule:Ruleset,
  {0b92ea24-6eb2-4fd3-8948-66890fc5c5c5}, !- Handle
  25C Lab no setback,                     !- Name
  ,                                       !- Schedule Type Limits Name
  ,                                       !- Default Day Schedule Name
  ,                                       !- Summer Design Day Schedule Name
  ;                                       !- Winter Design Day Schedule Name

OS:Schedule:Ruleset,
  {67740387-4fe7-4952-be05-c1656275de62}, !- Handle
  25C Conference no setback,              !- Name
  ,                                       !- Schedule Type Limits Name
  ,                                       !- Default Day Schedule Name
  ,                                       !- Summer Design Day Schedule Name
  ;                                       !- Winter Design Day Schedule Name

OS:Schedule:Ruleset,
  {9e96dd69-241a-4e0b-ac9e-f022ece9bec6}, !- Handle
  25C Gym no setback,                     !- Name
  ,                                       !- Schedule Type Limits Name
  ,                                       !- Default Day Schedule Name
  ,                                       !- Summer Design Day Schedule Name
  ;                                       !- Winter Design Day Schedule Name

OS:Schedule:Ruleset,
  {e85f7e07-1769-4e00-a3b7-9d57da7c94c7}, !- Handle
  25C Class no setback,                   !- Name
  ,                                       !- Schedule Type Limits Name
  ,                                       !- Default Day Schedule Name
  ,                                       !- Summer Design Day Schedule Name
  ;                                       !- Winter Design Day Schedule Name

OS:Schedule:Ruleset,
  {3f75378d-6d73-458d-82d3-c34bdc842793}, !- Handle
  25C Break Student no setback,           !- Name
  ,                                       !- Schedule Type Limits Name
  ,                                       !- Default Day Schedule Name
  ,                                       !- Summer Design Day Schedule Name
  ;                                       !- Winter Design Day Schedule Name

To find them I searched for , !- Default Day Schedule Name. Find them and delete them then you are good to go.