flow:
  - start|sl:filtered-ack:
sip_in:
  - 'ACK sip:[% invite_alias_scenarios_pbx_test.testuser1003.alias_numbers.0.phone_number %]@invite-alias.scenarios-pbx.test SIP/2.0'
  - 'From: <sip:[% scenarios.0.username %]@invite-alias.scenarios-pbx.test>;tag=[\w-]+'
  - 'To: <sip:[% invite_alias_scenarios_pbx_test.testuser1003.alias_numbers.0.phone_number %]@invite-alias.scenarios-pbx.test>;tag=[\w-]+'
  - 'CSeq: \d+ ACK'
  - 'Content-Length: 0'
sip_out: []
