Planning applications are shown on
Planning – Applications Search
on Powys Council's website.

Click on the above link,
then click on the "Simple" tab (if not already selected).

Type "Llangynog" (without the quotes) in the box labelled
"Enter a keyword, reference number, postcode or single line of an address",
then click "Search".

On the list that appears,
click on the link for the application you want.

Comments can be left, if within the statutory period.

Welsh planning policy is available at
Planning Policy Wales
on the Welsh Government's website.