Thanks for coming back on this Jamie.
I notice you might intend to change the battery anyway - personally, I wouldn’t - I would go through the charging and testing procedure first, and only change it if it proves to be at fault.
Come back to the forum when you’ve done that, and then we can address your hot starting issue.
Meanwhile, does the car appear to be heavier on fuel than it has been?
Kind regards,
Gareth.