Securing and Attaching Home Electrical Mast
Depending on how well you know the area under the siding, you may find that a Kindorf bracket pair will be the easiest to install. A U-bolt requires access to the rear to secure the nuts, which seems unlikely with your siding. It seems unlikely with any house covering system.

A Kindorf bracket is rather common in the electrical field, although until now, I was not aware that I knew the product.

You would have to be able to secure a slotted rail across the axis of the pipe currently in place, perhaps wedged between the siding and the pipe. You would need to locate studs into which the rail would be fastened.

The Kindorf brackets are similar to the prohibited pipe straps but more strongly constructed.



Even though the image above shows an L-bracket rail mount, the rails are available for surface mounting.

I think the most challenging part of this correction is to find the studs inside the wall.