Your count will always be right (ie you won't 'lose' posts), the individual page counts may be wrong.
As I understand it, the UBB software that the Ranch run on allows server side caching to reduce response times.
Therefore if you reply to a post on page A, your posts may show '70'. If you post elsewhere a few times and no-one posts on page A, page A will stay '70'. If you post again to page A, the previous post value and the new one will both be updated to the new post value eg '75' when the page is rebuilt...
DOM