100 Years of GCHQ - A quick afternoon puzzle!

Question

I'm off to the Science Museum London tomorrow, to the Exhibition celebrating 100 years of GCHQ. As such, they sent me a little reminder email this afternoon.

On the bottom of the email was the following code:

Bv qthv utj vzptu utjs wcfcn - fvza jf e nbvvn co utj avmsuhnva nqcf mtav!

I thought I would share with you lovely people!

Happy deciphering.

Note: I have no affiliation to the Science museum

Wanted to add a hint for anyone who wants to try and solve without looking below:

The word nbvvn is a hyperlink to the science museum twitter page

Answer 1

It is a:

Cryptogram

It says:

We hope you enjoy your visit - send us a tweet if you decrypted this code

I solved it by hand in Excel but you can use sites like:

quipqiup.com