Fix dates

templates/emails/receipt.txt

@@ -4,11 +4,11 @@ Hello {{ user.name }}!
 
 With Electromagnetic Field fast approaching, here are your tickets
 and some more details about the event. The gates will open at 10am on
-Thursday 2nd June {#- 2022 #} to allow you to set up and get comfortable, and our
+Thursday 30th May {#- 2024 #} to allow you to set up and get comfortable, and our
 programme of content kicks off at midday on Friday.
 
 Unless you're helping out with teardown, you should aim to leave by
-midday on Monday 6th June {#- 2022 #}.
+midday on Monday 3rd June {#- 2024 #}.
 
 {% include 'emails/receipt-blurb.txt' %}