Please navigate to your Sku Grid Settings. Click on General Repricer. On this screen you will see that there are 2 options. 

One is called Safe Repricing and one is called Super Safe Repricing. You only ever need to have 1 of these options turned on or not use these settings at all. With both Safe and Super Safe Repricing, if either one is selected, when an item goes out of stock and then back in stock, these settings will cause Sku Grid to wait until the item has remained in stock for a full 24 hours before allowing it to be put back in stock. This would be the reason why you might notice an item came back in stock, and it's been past your normal repricing time frame, but the item has not become available yet. If this is the case, you can turn off these options and force reprice the item. There is only 1 difference between the two settings. And that is how they handle price decreases. 

With Safe Repricing, if a price decreases but is less than 60% of the average selling price over the last 3 days, then skugrid would not decrease your price. With Super Safe Repricing, if a price decreases, but is less than the average price for the last 24 hours, then skugrid would not decrease your price. That is the difference between the 2 options -- they both handle in and out of stock the same, but handle price drops slightly differently.

These settings are here to protect you when suppliers have site glitches or unstable prices or stock. Basically, it waits until the changes stabilize before changing your item. You can choose one option or the other or none at all if you prefer to have your items change once observed and according to your repricing/checker time.