This is probably one you are going to have to contact eBay about. I took a look at one of your listings. I am in the US but the shipping timelines look like they are about what you described. However if I change my location to Canada the timeline is shorter and there are different...
.itemizedReturnShippingCost .amount.exchangeRate string Conditionally This field shows the exchange rate used to convert the amount in the convertedFromValue field to amount in the value field. This field is only returned when eBay does a currency version. returnShippingCostInfo .carriers.shippingCo...
9, wherein different weights are assigned to the shipping delivery geographic location, the shipping origin geographic location, historical delivery estimates, the shipping carrier delivery estimate, the shipping season, and external factors to compute the personalized delivery time estimate for the buyer...