Apparently Spider-Man: Homecoming went under reshoots recently as Robert Downey Jr. took to his social networks to post an image of himself along with Tom Holland and Jon Favreau, who returns as Happy Hogan.
Reshoots are pretty common with these big budget movies, so there isn't anything to worry about.
Update: Tom Holland also posted a pic.
Killer trio... #BTS #IronMan #Spiderman #marvel #spidermanhomecoming #secretshoot
"Spider-Man: Homecoming" has a July 7, 2017 release directed by Jon Watts starring Tom Holland, Zendaya, Michael Keaton, Donald Glover, Jacob Batalon, Laura Harrier, Tony Revolori, Tyne Daly, Bokeem Woodbine, with Marisa Tomei, and Robert Downey Jr.¬†
A young Peter Parker/Spider-Man (Tom Holland), who made his sensational debut in¬†Captain America: Civil War, begins to navigate his newfound identity as the web-slinging¬†super hero¬†in¬†Spider-Man: Homecoming.¬† Thrilled by his experience with the¬†Avengers, Peter returns home, where he lives with his Aunt May (Marisa Tomei), under the watchful eye of his new mentor Tony Stark (Robert Downey, Jr.). Peter tries to fall back into his normal¬†daily routine¬†‚Äď distracted by thoughts of proving himself to be more than¬†just¬†your friendly neighborhood Spider-Man ‚Äď but when the Vulture (Michael Keaton) emerges as a new villain, everything that Peter holds most important will be threatened.