Sorry to resurrect this thread, but it's the thread that google's AI is using to give advice on this, so I guess I'll add the full info, having learned the last detail today...
A standard grom bomb (power play 'containment missile') resets the FSD causing a 'long' reboot of 17 seconds, however the containment effect has a cooldown and can only be applied every 29 seconds. Adding the FSD interrupt engineering special effect, adds approximately 2 seconds to the reboot time for a total of 19 seconds.
It takes 10 seconds to charge a high wake, so a grom bomb with FSD interrupt can 'almost' stunlock you. You need to initiate the highwake within ONE SECOND (in reality you may have a few more, but technically, it's 1 second, assuming perfect play) of the FSD becoming active again and have no masslock factor at all in order to escape with a high wake.
If you are facing a player with grom bombs with FSD interrupt applied, you should low wake at the earliest opportunity, as soon as you are in SC, drop to normal space again and initiate a high wake to the nearest system. It is EXTREMELY risky to try to high wake in this scenario. If you fail the timing by 1 second, they get an extra 30 seconds to kill you.