What is the best and quickest delivery company into fulfilment centres in the UK?

I’m in the UK and sent my first FBA stock over to a fulfilment centre about a month ago using Amazon’s preferred delivery company which was UPS.

The stock was held by UPS for about 10 days before it was delivered, and a further 20 to be processed by the warehouse.

I used to work for a large competitor of UPS, and they had trailers going into Amazon Fulfilment centres daily, with the exception of maybe holding trailers over weekends or if delivery slots were missed/rejected.

I’ve unfortunately had to close one of my storage units down this weekend, and have a mountain of stock I’d like to send over to Amazon ready for the Christmas rush.

I’m just wondering if anybody else in the UK has better and quicker service with other delivery companies?