Exactly.
The verses only support one second coming.
A normative literal interpretation of the text shows that these two verses, written by the same author in the same letter, are talking about the same event.
1 Thessalonians 3:13
13 To the end he may stablish your hearts unblameable in holiness before God, even our Father, at the coming of our Lord Jesus Christ with all his saints. |
1 Thessalonians 4:15
15 For this we say unto you by the word of the Lord, that we which are alive and remain unto the coming of the Lord shall not prevent them which are asleep. |
The same author clarified who the saints were that come with Jesus in the second letter to the same audience.
2 Thessalonians 1:7
7 And to you who are troubled rest with us, when the Lord Jesus shall be revealed from heaven with his mighty angels, |