blocks forgetting region placement

Question

So i've run into an issue with a block somehow losing its region placement somewhat randomly. For background the block is very simple

        $blocks['tx_leftcol_block'] = array(
      'info' => t('Tx leftcol block'),
    );

The content isn't the issue, as even with some static content this block disappears.

On the blocks overview page this is placed on a custom region called tx sidebar (its a sidebar for certain pages). The weird part is other blocks show fine in this sidebar and dont lose placement, but for some reason this block gets disabled randomly, i.e. every couple of login/logouts it hides, or after a certain amount of time.

Any ideas what could be the cause?

Answer 1

It turned out to be a caching issue which i resolved by suing the block_flush_caches method.