We can only guess as to what will happen in the future. However, it is unlikely there will be a major layoff anytime soon. Not before Oct 2018.
The last one in 1Q was fairly significant. Many people (including some "bleed-blue" execs) have had it and are leaving on their own. The internal organizations are shaken up. At the end of a meeting, even some clients wonder if they will get to see the same IBM employees in the next meeting. IBM is hopefully not going to make all this even worse with another major layoff soon.
So, this last one will carry IBM for another 2 quarters. By that time, the environment would have stabilized but numbers would likely still be bad. So, another layoff may be executed before the end of the year.