A connecting rod bearing would get progressively, and quickly, worse to the point of destruction. If the noise continues for more than 20 miles, it isn't a rod bearing, that's for sure. It is piston slap. Unlike older engines that develop piston slap, the B230 engine with its very short (almost non-existent) piston skirt sounds a lot "heavier" as the contact point is not the opposite skirt, but the top of the piston at the ring lands hitting the bore.
To some extent the noise, and the damage, is benign, although eventually the rings begin to lose good contact with the cylinder wall and you will get blowby and oil consumption. Just a bad design from a company that used to know better.