It is still a stretch for a bolt hole to be in a offshore rig. A compliant tower is anchored to the seafloor, but they are designed to flex and that would seem to be contrary to long term survivability. That leaves us with a steel jacket fixed platform.
While it is conceivable that you could build a bolt hole inside the jacket of a leg prior to final construction, the jacket does get most of its strength from being round rolled steel welded together with the smaller braces welded between them. This would mean that everything would have to be inside the bolt hole before the jacket was finished and that you could not update the contents of it once sealed. There is also the problem of it jacket being constructed on its side and then having one end slowly submerged to stand it after it is towed to the final location. This means that everything has to be very firmly strapped down to the "floor", including all the vehicles, since it will be on its side for a decent amount of time. These straps would likely entail some sort of steel bracing, brackets and large explosive bolts for the vehicles. Assuming there is such a bolt hole, the normal wake up and launch would be thaw the personnel, have them detonate the bolts to free the vehicles, and then punch the button to activate the thermite charges to burn the door through the jacket with a laser or cutting torch in reserve to use if the thermite fails to open the side correctly for any reason.
This just seems like a lot of work when a more "conventional" design that is used in hundreds of location would just make more sense from an economics and design standpoint.
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