Welcome to the board!
As you have been reading the forum for a while now, I am sure you know the "hotly contested topic" of Foreigner with and without Mick, current versus previous lineup, et. al. And yes, Foreigner fans, and music fans as a whole, are glad that one of the pioneers of rock music, Mr. Mick Jones, is returning to good health.
While there are varying opinions on this topic, I want to stick to your questions about the Soundtrack of Summer Tour.
For the past few years, as Mick was recovering and gaining strength to repair his health, you are correct- he would not attend many shows, just making an occasional appearance at a few shows here and there, and just doing interviews. Remember- he is 68, and recovery to "form" takes longer in the latter years in life.
I have been reading the reviews from the concerts both in the media, and on the bands websites, and perusing the pictures, and it is my understanding that he has been, and is fully prepared to perform during this tour and for the remainder of the tour, and has been performing with the band after they are a few songs into the set at every stop thus far. After a few songs pass, Kelly will introduce Mick, the crowd whips into an even more frenzy, and the Juke Box Hero himself performs the remainder of the set. The reviews are nothing but spectacular!
I am by no means affiliated with Foreigner, nor am I speaking for the band, I am not a representative of the band, I am not a forum admin, nor a member of the media. I am just a huge fan of the past and the present lineup, and sharing what I have found thus far, as I have been following this tour very closely.
I would be curious to see if anyone could add to this, who have attended some of the shows on the tour thus far. They would be able to confirm or deny this.
However Rob G, I would be confident that if you attend the show tomorrow, you will most likely get Mick Jones for your dollar!
Lastly, to anyone who may follow up this comment, let's try to keep this thread about the Soundtrack of Summer tour, as that is the main topic here. Let's try not to dilute it into a Mick vs Lou debate, old vs new lineup argument, etc. This right here isn't about that.
Hope this helps, Rob G!
PS- Let's get some reviews of the tour, fellow Foreigner friends!!