I do hope that that's the plan, no reason why it shouldn't be but A boards aren't that common, or are they? First I heard of them was Birmingham New St.
They have - incidents more than accidents - it takes a degree of skill to have an accident with a train that's blown its horn and is accelerating from stop. One incident saw a bin lorry reversed whilst the train was stopped, with its banksman waving the bin lorry back (Llanion Crossing, 200 yds from Pembroke Dock) as if the train was letting it go.
An actual accident had a taxi slam in to the rear bogie of a 153 at the Beavers Hill crossing (for points not prison, nor lost licence). The taxi driver said he had misjudged the speed of the train (presumably thought it was going faster than it actually was) -
https://www.bbc.co.uk/news/uk-wales-45260451
They had a rather expensive plan to close Llanion Crossing, diverting paths, building footpaths, acquiring land (see plan at
https://www.networkrail.co.uk/wp-co...-routes-east-and-west-of-Llanion-Cottages.pdf) in 2020. The new idea sounds much more cost effective, and presumably the other idea dropped.