I doubt that very much in such a promotion driven industry. In fact the industry survives and only thrives on promotion. Not even a still? Cmon.
I think the lack of promotional images is a function of the reshoots and tight schedule Ron Howard has been working to lock the film up. They used a lot of promo images and video for Rogue One that never appeared in the final cut if the film which caused some confusion. Probably best to let Ron finish and make sure they are using the right stuff. And if the choice is no Solo media releases before TLJ is done then that’s going to apply to all of it except a generic teaser poster.