R D S wrote:
On Tue, 06 Sep 2016 17:29:13 +0100, Tim Watts wrote:

What is the wall construction? (As there are several types that "are
not solid")

Of course.

It's a wall that *should be* solid, brick, rest of it was nice to
drill into.

You've hit the brick joints, try moving the bracket a few inches left or
right and trying again, fill holes with sandable filler and paint