He also gets on and no confused, says d's as b's and b's and d's when reading, on instead of no and today I watched him looking at the word 'tap' and saying 'p-a-t. No, t or p or is it t' etc. I have raised it with his teacher but she says it's nothing to be concerned about................
Where do some teachers get their ideas from
Of course it is something to be concerned about. Everytime he gets something wrong like that he is reinforcing the wrong learning and making it more and more difficult to correct it.
Reading words from right to left is easy to deal with. Just get a piece of card and cover the word, reveal it grapheme by grapheme, thus making sure that he decodes it from L to R every time. Don't stress about him sounding out every word, let him do it for a while as that will reinforce the development of automatic L to R eye tracking. I'm sorry but I suspect that word 'reversals' like the ones you describe are often a product of insistence on reading words 'on sight' too early and not allowing for enough sounding out and blending to develop automaticity and correct tracking.
Letter reversals need lots of practice of writing the letter correctly while saying its 'sound'. Don't let him start to write both his b's & d's from the top of the ascender. He'll get to the bottom and not remember which way to go next! 'd' starts with the 'round', 'b' starts with the ascender. Letters are always written in a L to R direction (when correctly formed)
When reading 'd' and 'b': 'd' starts with mouth open (the 'round' bit) so when he sees 'round' first he opens his mouth to say the sound. 'b' starts with a straight line, like a closed mouth (I know, sideways on..). When he sees a straight line first he closes his mouth to say the sound. This works with 'p' and 'q' too.