FYI, AWS offers free Egress when leaving them (because they were forced to be EU regulation, but they chose to offer it globally):

https://aws.amazon.com/blogs/aws/free-data-transfer-out-to-i...

But. Don't leave it until the last minute to talk to them about this. They don't make it easy, and require some warning (think months, IIRC)

Extremely useful information - unfortunately I just assumed this didn't apply to me because I am in the UK and not the EU. Another mistake, though given it's not huge amounts of money I will chalk it up to experience.

Hopefully someone else will benefit from this helpful advice.