When listing on Amazon, you should always consider Amazon’s throttling. Amazon limits the number of requests to their API from a single Merchant ID as 30 requests per hour. On Amazon Europe, this limitation is split across 5 European marketplaces. It means you can send only 6 bulk updates to each of the 5 European marketplaces in a 1-hour period. If you hit these limits, you might get throttled.
Let’s say you are selling your products on all 5 European marketplaces and want to update the product quantity, price, details, images, and variations at the same time. M2E Pro will have to use 5 of the 6 available feeds to make these updates. Therefore, you’ll need to wait up to 1 hour to update your products next time. This delay is critical for big-sized inventories or peak season sales.
That is why you need to be thoughtful when configuring your Synchronization Rules.
The good practice is to keep Revise by Quantity and Price options constantly enabled, while all the rest Revise options consider optional. For example, you may need to update your product details or images if you are an ASIN creator or Private Label owner. Otherwise, it is better to disable Details and Image Revise options. It will allow M2E Pro to use available feeds for the product quantity and price updates.