I was just wondering------what is the appropriate/reasonable time to start writing journal articles in the PhD journey? Is 1-6 months too early?

What has been your direct experiences and how would you do things differently?

I think you must first state what you're doing PhD in. Because in my area you have to make experiments first so you have anything to write about :D

It's in Social Science, a lot of reading is expected etc. Which brings me to another question if one publishes too early what r the implications if any?

The only disadvantage is that by waiting you may create generate a better publication.
Otherwise, go ahead and do it!